Index of Topics

- A -
a
Adding Modules to a Library File
The Alternate Addressing Form Option - "fi"
Always Create a New Library - "n" Option
Applying a Patch
Approximate Timestamp Matching (.FUZZY)
Assembler Directives, Operators and Assembly Opcodes
The Assembly Format Option - "a"
Automatic Dependency Detection (.AUTODEPEND)

- B -
b

- C -
c
Cache Search Path (.OPTIMIZE)
Calling convention
Case Sensitive Symbol Names - "c" Option
Changing the Internal Label Character - "i=<char>"
Command Line Options
Command List Directives
Command List Execution
Command Lists
Commands from a File or Environment Variable
Compatibility Between Open Watcom Make and UNIX Make
Conditional Processing
Creating a Listing File - "l" Option
Creating Import Libraries
Creating Import Library Entries

- D -
d
Default Command List (.DEFAULT)
Defining Recognized File Extensions (.EXTENSIONS)
Defining Recognized File Extensions (.SUFFIXES)
Deleting Modules from a Library File
Dependency Declarations
Diagnostic Messages
Disable Implicit Rules (.BLOCK)
Display C++ Mangled Names - "m" Option
Double Colon Explicit Rules

- E -
e
echo command
Erasing Targets After Error (.ERASE)
Error Action (.ERROR)
An Example
Exe2bin Messages
Explode Library File - "x" Option
The External Symbols Option - "e"
Extracting a Module from a Library File

- F -
f
Far Call Optimizations for Non-Open Watcom Object Modules
File Inclusion
Final Commands (.AFTER)
for command
The FPU emulator fixups Option - "ff"

- G -
Generating Imports - "i" Option

- H -
h

- I -
i
IDE2MAKE Operation
The IDE2MAKE Utility
if command
Ignoring Dependent Timestamps (.ALWAYS)
Ignoring Errors (.CONTINUE)
Ignoring Return Codes (.IGNORE)
Ignoring Target Timestamp (.EXISTSONLY)
Ignoring Target Timestamp (.NOCHECK)
Implicit Rules
Initial Commands (.BEFORE)

- K -
k

- L -
l
Librarian Error Messages
The Listing Option - "l[=<list_file>]"
Loading Dynamic Link Libraries

- M -
m
Macros
Make internal commands
MAKEINIT File
Minimising Target Timestamp (.JUST_ENOUGH)
mkdir command
ms
Multiple Dependents
Multiple Rules
Multiple Targets

- N -
n
Name Command Sequence (.PROCEDURE)
Naming convention
The No Instruction Name Pseudonyms Option - "fp"
The No Register Name Pseudonyms Option - "fr"

- O -
o
The Object File Disassembler
Open Watcom "C" name mangler
The Open Watcom Assembler
Open Watcom Assembler Diagnostic Messages
Open Watcom Assembler Specific
The Open Watcom C/C++ Compile and Link Utility
The Open Watcom C/C++ POSIX-like Compiler Driver
Open Watcom Compile and Link Options Summary
The Open Watcom Exe2bin Utility
The Open Watcom Exe2bin Utility Command Line
The Open Watcom Far Call Optimization Enabling Utility
The Open Watcom Library Manager
The Open Watcom Library Manager Command Line
Open Watcom Library Manager Module Commands
Open Watcom Library Manager Options
Open Watcom Make Command Line Format
Open Watcom Make Diagnostic Messages
Open Watcom Make Options Summary
Open Watcom Make Reference
The Open Watcom Make Utility
The Open Watcom Patch Utility
The Open Watcom Strip Utility
The Open Watcom Strip Utility Command Line
Operate Quietly - "q" Option
Operate Verbosely - "v" Option
Optimization of Far Calls
owcc Command Line Examples
owcc Command Line Format
owcc Options Summary

- P -
p
Preprocessing Directives
Preserving Targets (.PRECIOUS)
Preserving Targets After Error (.HOLD)
The Public Symbols Option - "p"

- Q -
q

- R -
r
Re-Checking Target Timestamp (.RECHECK)
Replacing Modules in a Library File
Retain C++ Mangled Names - "m"
rm command
rmdir command

- S -
s
set command
sn
The Source Option - "s[=<source_file>]"
Special Macros
Specify Output Directory - "d" Option
Specify Output Format - "f" Option
Specifying a Library Record Size - "p" and "pa" Options
Specifying an Output File Name - "o" Option
Specifying Explicitly Updated Targets (.EXPLICIT)
Strip Line Number Records - "s" Option
Strip Utility Messages
Suppress Creation of Backup File - "b" Option
Suppressing Terminal Output (.SILENT)

- T -
t
Targets Without Any Dependents (.SYMBOLIC)
The Touch Utility
Trim Module Name - "t" Option

- U -
u
Unsupported Directives
Updating Targets Multiple Times (.MULTIPLE)
The Uppercase Instructions/Registers Option - "fu"

- V -
v

- W -
WCL/WCL386 Command Line Examples
WCL/WCL386 Command Line Format
WCL/WCL386 Environment Variables
WTOUCH Operation

- Y -
y

- Z -
z

The Open Watcom C/C++ Compile and Link Utility


The Open Watcom C/C++ Compile and Link Utility is designed for generating applications, simply and quickly, using a single command line.  On the command line, you can list source file names as well as object file names.  Source files are either compiled or assembled based on file extension; object files and libraries are simply included in the link phase.   Options can be passed on to both the compiler and linker.

WCL/WCL386 Command Line Format


The format of the command line is:

     
     WCL [files] [options]
     WCL386 [files] [options]

The square brackets [ ] denote items which are optional.
WCL
is the name of the Open Watcom Compile and Link utility that invokes the 16-bit compiler.

WCL386
is the name of the Open Watcom Compile and Link utility that invokes the 32-bit compiler.

The files and options may be specified in any order.  The Open Watcom Compile and Link utility uses the extension of the file name to determine if it is a source file, an object file, or a library file.  Files with extensions of "OBJ" and "LIB" are assumed to be object files and library files respectively.  Files with extensions of "ASM" are assumed to be assembler source files and will be assembled by the Open Watcom Assembler.  Files with any other extension, including none at all, are assumed to be C/C++ source files and will be compiled.  Pattern matching characters ("*" and "?") may be used in the file specifications.

If no file extension is specified for a file name then the Open Watcom Compile and Link utility will check for a file with one of the following extensions.

     
     Order   Name.Ext        Assumed to be
     -----   --------        ---------------
       1.    file.ASM        Assembler source code
       2.    file.CXX        C++ source code
       3.    file.CPP        C++ source code
       4.    file.CC         C++ source code
       5.    file.C          C   source code

It checks for each file in the order listed.  By default, the Open Watcom Assembler will be selected to compile files with the extension "ASM".  By default, the Open Watcom C++ compiler will be selected to compile files with any of the extensions "CXX", "CPP" or "CC".  By default, the Open Watcom C compiler will be selected to compile a file with a "C" extension.  The default selection of compiler can be overridden by the "cc" and "cc++" options, described below.

Options are prefixed with a slash (/) or a dash (-) and may be specified in any order.  Options can include any of the Open Watcom C/C++ compiler options plus some additional options specific to the Open Watcom Compile and Link utility.   A summary of options is displayed on the screen by simply entering the "WCL" or "WCL386" command with no arguments.
General options:
Description:

c
compile the files only, do not link them

cc
treat source files as C code

cc++
treat source files as C++ code

y
ignore the WCL/WCL386 environment variable
Compiler options:
Description: 

0
(16-bit only) 8088 and 8086 instructions (default for 16-bit)

1
(16-bit only) 188 and 186 instructions

2
(16-bit only) 286 instructions

3
(16-bit only) 386 instructions

4
(16-bit only) 486 instructions

5
(16-bit only) Pentium instructions

6
(16-bit only) Pentium Pro instructions

3r
(32-bit only) generate 386 instructions based on 386 instruction timings and use register-based argument passing conventions

3s
(32-bit only) generate 386 instructions based on 386 instruction timings and use stack-based argument passing conventions

4r
(32-bit only) generate 386 instructions based on 486 instruction timings and use register-based argument passing conventions

4s
(32-bit only) generate 386 instructions based on 486 instruction timings and use stack-based argument passing conventions

5r
(32-bit only) generate 386 instructions based on Intel Pentium instruction timings and use register-based argument passing conventions (default for 32-bit)

5s
(32-bit only) generate 386 instructions based on Intel Pentium instruction timings and use stack-based argument passing conventions

6r
(32-bit only) generate 386 instructions based on Intel Pentium Pro instruction timings and use register-based argument passing conventions

6s
(32-bit only) generate 386 instructions based on Intel Pentium Pro instruction timings and use stack-based argument passing conventions

aa
(C only) allow non-constant initializers for local aggregates or unions

ad[=<file_name>]
generate make style automatic dependency file

adbs
force path separators generated in auto-dependency files to backslashes

add[=<file_name>]
specify source dependency name generated in make style auto-dependency file

adhp[=<file_name>]
specify path to use for headers with no path given

adfs
force path separators generated in auto-dependency files to forward slashes

adt[=<target_name>]
specify target name generated in make style auto-dependency file

bc
build target is a console application

bd
build target is a Dynamic Link Library (DLL)

bg
build target is a GUI application

bm
build target is a multi-thread environment

br
build target uses DLL version of C/C++ run-time libraries

bt[=<os>]
build target for operating system <os>

bw
build target uses default windowing support

d0
(C++ only) no debugging information

d1
line number debugging information

d1+
(C only) line number debugging information plus typing information for global symbols and local structs and arrays

d2
full symbolic debugging information

d2i
(C++ only) d2 and debug inlines; emit inlines as external out-of-line functions

d2s
(C++ only) d2 and debug inlines; emit inlines as static out-of-line functions

d2t
(C++ only) full symbolic debugging information, without type names

d3
full symbolic debugging with unreferenced type names

d3i
(C++ only) d3 plus debug inlines; emit inlines as external out-of-line functions

d3s
(C++ only) d3 plus debug inlines; emit inlines as static out-of-line functions

d<name>[=text]
preprocessor #define name [text]

d+
allow extended -d macro definitions

db
generate browsing information

e<number>
set error limit number (default is 20)

ecc
set default calling convention to __cdecl

ecd
set default calling convention to __stdcall

ecf
set default calling convention to __fastcall

ecp
set default calling convention to __pascal

ecr
set default calling convention to __fortran

ecs
set default calling convention to __syscall

ecw
set default calling convention to __watcall (default)

ee
call epilogue hook routine

ef
use full path names in error messages

ei
force enum base type to use at least an int

em
force enum base type to use minimum

en
emit routine name before prologue

ep[<number>]
call prologue hook routine with number of stack bytes available

eq
do not display error messages (they are still written to a file)

er
(C++ only) do not recover from undefined symbol errors

et
Pentium profiling

ew
(C++ only) generate less verbose messages

ez
(32-bit only) generate Phar Lap Easy OMF-386 object file

fc=<file_name>
(C++ only) specify file of command lines to be batch processed

fh[q][=<file_name>]
use precompiled headers

fhd
store debug info for pre-compiled header once (DWARF only)

fhr
(C++ only) force compiler to read pre-compiled header

fhw
(C++ only) force compiler to write pre-compiled header

fhwe
(C++ only) don't include pre-compiled header warnings when "we" is used

fi=<file_name>
force file_name to be included

fo=<file_name>
set object or preprocessor output file specification

fpc
generate calls to floating-point library

fpi
(16-bit only) generate in-line 80x87 instructions with emulation (default)
(32-bit only) generate in-line 387 instructions with emulation (default)

fpi87
(16-bit only) generate in-line 80x87 instructions
(32-bit only) generate in-line 387 instructions

fp2
generate in-line 80x87 instructions

fp3
generate in-line 387 instructions

fp5
generate in-line 80x87 instructions optimized for Pentium processor

fp6
generate in-line 80x87 instructions optimized for Pentium Pro processor

fpd
enable generation of Pentium FDIV bug check code

fpr
generate 8087 code compatible with older versions of compiler

fr=<file_name>
set error file specification

ft
try truncated (8.3) header file specification

fti
(C only) track include file opens

fx
do not try truncated (8.3) header file specification

fzh
(C++ only) do not automatically append extensions for include files

fzs
(C++ only) do not automatically append extensions for source files

g=<codegroup>
set code group name

h{w,d,c}
set debug output format (Open Watcom, Dwarf, Codeview)

i=<directory>
add directory to list of include directories

j
change char default from unsigned to signed

k
(C++ only) continue processing files (ignore errors)

m{f,s,m,c,l,h}
memory model
mf=flat
ms=small
mm=medium
mc=compact
ml=large
mh=huge
(default is "ms" for 16-bit and Netware, "mf" for 32-bit)

nc=<name>
set name of the code class

nd=<name>
set name of the "data" segment

nm=<name>
set module name different from filename

nt=<name>
set name of the "text" segment

o{a,b,c,d,e,f,f+,h,i,i+,k,l,l+,m,n,o,p,r,s,t,u,x,z}
control optimization

pil
preprocessor ignores #line directives

p{e,l,c,w=<num>}
preprocess file only, sending output to standard output
"c" include comments
"e" encrypt identifiers (C++ only)
"l" include #line directives
"w=<num>" wrap output lines at <num> columns (zero means no wrap)

q
operate quietly

r
save/restore segment registers

ri
return chars and shorts as ints

s
remove stack overflow checks

sg
generate calls to grow the stack

st
touch stack through SS first

t=<num>
(C++ only) set tab stop multiplier

u<name>
preprocessor #undef name

v
output function declarations to .def file (with typedef names)

vc...
(C++ only) VC++ compatibility options

w<number>
set warning level number (default is w1)

wcd=<num>
warning control:  disable warning message <num>

wce=<num>
warning control:  enable warning message <num>

we
treat all warnings as errors

wo
(C only) (16-bit only) warn about problems with overlaid code

wx
set warning level to maximum setting

x
preprocessor ignores environment variables

xd
(C++ only) disable exception handling (default)

xdt
(C++ only) disable exception handling (same as "xd")

xds
(C++ only) disable exception handling (table-driven destructors)

xr
(C++ only) enable RTTI

xs
(C++ only) enable exception handling

xst
(C++ only) enable exception handling (direct calls for destruction)

xss
(C++ only) enable exception handling (table-driven destructors)

xx
ignore default directories for file search (.,../h,../c,...)

z{a,e}
disable/enable language extensions (default is ze)

zastd=<standard>
use specified ISO/ANSI language standard

za99
use ISO/ANSI C99 language standard; deprecated, use zastd=c99

zam
disable all predefined old extension macros (keyword macros, non-ISO names)

zat
(C++ only) disable alternative tokens

zc
place literal strings in code segment

zd{f,p}
allow DS register to "float" or "peg" it to DGROUP (default is zdp)

zdl
(32-bit only) load DS register directly from DGROUP

zev
(C only, Unix extension) enable arithmetic on void derived types

zf
(C++ only) let scope of for loop initialization extend beyond loop

zf{f,p}
allow FS register to be used (default for all but flat memory model) or not be used (default for flat memory model)

zfw
generate FWAIT instructions on 386 and later

zg
output function declarations to .def (without typedef names)

zg{f,p}
allow GS register to be used or not used

zk0
double-byte char support for Kanji

zk0u
translate Kanji double-byte characters to UNICODE

zk1
double-byte char support for Chinese/Taiwanese

zk2
double-byte char support for Korean

zkl
double-byte char support if current code page has lead bytes

zku=<codepage>
load UNICODE translate table for specified code page

zl
suppress generation of library file names and references in object file

zld
suppress generation of file dependency information in object file

zlf
add default library information to object files

zls
remove automatically inserted symbols (such as runtime library references)

zm
place each function in separate segment (near functions not allowed)

zmf
place each function in separate segment (near functions allowed)

zp{1,2,4,8,16}
set minimal structure packing (member alignment)

zpw
output warning when padding is added in a struct/class

zq
operate quietly

zri
inline floating point rounding code

zro
omit floating point rounding code

zs
syntax check only

zt<number>
set data threshold (default is 32767 for 16-bit and 2147483647 for 32-bit)

zu
do not assume that SS contains segment of DGROUP

zv
(C++ only) enable virtual function removal optimization

zw
Microsoft Windows prologue/epilogue code sequences

zW
(16-bit only) Microsoft Windows optimized prologue/epilogue code sequences

zWs
(16-bit only) Microsoft Windows smart callback sequences

zz
remove "@size" from __stdcall function names (10.0 compatible)

See the Open Watcom C/C++ User's Guide for a full description of compiler options.
Linker options:
Description:

bcl=<system name>
Compile and link for the specified system name.  See the section for link option 'l=' below and the linker user guide for available system names.  This is equivalent to specifying -bt=<system name> and -l=<system name>.

k<stack_size>
set stack size

fd[=<directive_file>]
keep directive file and, optionally, rename it (default name is "__WCL__.LNK").

fe=<executable>
name executable file

fm[=<map_file>]
generate map file and name it (optional)

lp
(16-bit only) create an OS/2 protected-mode program

lr
(16-bit only) create a DOS real-mode program

l=<system_name>
link a program for the specified system.  Among the supported systems are:
286
16-bit DOS executables (synonym for "DOS") under DOS, NT and Linux
16-bit OS/2 executables (synonym for "OS2") under 32-bit OS/2 hosted OS/2 session

386
32-bit DOS executables (synonym for "DOS4G") under DOS
32-bit NT character-mode executables (synonym for "NT") under Windows NT
32-bit OS/2 executables (synonym for "OS2V2") under 32-bit OS/2 hosted OS/2 session
32-bit Linux executables (synonym for "LINUX") under Linux

CAUSEWAY
32-bit Causeway DOS Extender executables

COM
16-bit DOS "COM" files

DOS
16-bit DOS executables

DOS4G
32-bit Tenberry Software DOS Extender executables

DOS4GNZ
32-bit Tenberry Software DOS Extender non-zero base executables

NETWARE
32-bit Novell NetWare 386 NLMs

NOVELL
32-bit Novell NetWare 386 NLMs (synonym for NETWARE)

NT
32-bit Windows NT character-mode executables

NT_DLL
32-bit Windows NT DLLs

NT_WIN
32-bit Windows NT windowed executables

OS2
16-bit OS/2 V1.x executables

OS2_DLL
16-bit OS/2 DLLs

OS2_PM
16-bit OS/2 PM executables

OS2V2
32-bit OS/2 executables

OS2V2_DLL
32-bit OS/2 DLLs

OS2V2_PM
32-bit OS/2 PM executables

PHARLAP
32-bit PharLap DOS Extender executables

PMODEW
32-bit PMODE/W DOS Extender executables

QNX
16-bit QNX executables

QNX386
32-bit QNX executables

TNT
32-bit Phar Lap TNT DOS-style executable

WIN386
32-bit extended Windows 3.x executables/DLLs

WIN95
32-bit Windows 9x executables/DLLs

WINDOWS
16-bit Windows executables

WINDOWS_DLL
16-bit Windows Dynamic Link Libraries

X32R
32-bit FlashTek (register calling convention) executables

X32RV
32-bit FlashTek Virtual Memory (register calling convention) executables

X32S
32-bit FlashTek (stack calling convention) executables

X32SV
32-bit FlashTek Virtual Memory (stack calling convention) executables

These names are among the systems identified in the Open Watcom Linker initialization file, "WLSYSTEM.LNK".   The Open Watcom Linker "SYSTEM" directives, found in this file, are used to specify default link options for particular (operating) systems.  Users can augment the Open Watcom Linker initialization file with their own system definitions and these may be specified as an argument to the "l=" option.  The "system_name" specified in the "l=" option is used to create a "SYSTEM system_name" Open Watcom Linker directive when linking the application.

@<directive_file>
include additional directive file

"linker directives"
allows use of any linker directive

WCL/WCL386 Environment Variables


The WCL environment variable can be used to specify commonly used WCL options.  The WCL386 environment variable can be used to specify commonly used WCL386 options.  These options are processed before options specified on the command line. 

Example:

     C>set wcl=-d1 -ot
     C>set wcl386=-d1 -ot

The above example defines the default options to be "d1" (include line number debugging information in the object file), and "ot" (favour time optimizations over size optimizations).

Whenever you wish to specify an option that requires the use of an "=" character, you can use the "#" character in its place.  This is required by the syntax of the "SET" command.

Once the appropriate environment variable has been defined, those options listed become the default each time the WCL or WCL386 command is used.

The WCL environment variable is used by WCL only.  The WCL386 environment variable is used by WCL386 only.  Both WCL and WCL386 pass the relevant options to the Open Watcom C/C++ compiler and linker.  This environment variable is not examined by the Open Watcom C/C++ compiler or the linker when invoked directly.

Hint:  If you are running DOS and you use the same WCL or WCL386 options all the time, you may find it handy to place the "SET WCL" or "SET WCL386" command in your DOS system initialization file, AUTOEXEC.BAT.  If you are running OS/2 and you use the same WCL or WCL386 options all the time, you may find it handy to place the "SET WCL" or "SET WCL386" command in your OS/2 system initialization file, CONFIG.SYS.

WCL/WCL386 Command Line Examples


For most small applications, the WCL or WCL386 command will suffice.  We have only scratched the surface in describing the capabilities of the WCL and WCL386 commands.  The following examples describe the WCL and WCL386 commands in more detail.

Suppose that your application is contained in three files called apdemo.c, aputils.c, and apdata.c.   We can compile and link all three files with one command.

Example 1:

     C>wcl -d2 apdemo.c aputils.c apdata.c
     C>wcl386 -d2 apdemo.c aputils.c apdata.c

The executable program will be stored in apdemo.exe since apdemo appeared first in the list.  Each of the three files is compiled with the "d2" debug option.  Debugging information is included in the executable file.

We can issue a simpler command if the current directory contains only our three C/C++ source files.

Example 2:

     C>wcl -d2 *.c
     C>wcl386 -d2 *.c

WCL or WCL386 will locate all files with the ".c" filename extension and compile each of them.  The name of the executable file will depend on which of the C/C++ source files is found first.  Since this is a somewhat haphazard approach to naming the executable file, WCL and WCL386 have an option, "fe", which will allow you to specify the name to be used.

Example 3:

     C>wcl -d2 -fe=apdemo *.c
     C>wcl386 -d2 -fe=apdemo *.c

By using the "fe" option, the executable file will always be called apdemo.exe regardless of the order of the C/C++ source files in the directory.

If the directory contains other C/C++ source files which are not part of the application then other tricks may be used to identify a subset of the files to be compiled and linked.

Example 4:

     C>wcl -d2 -fe=apdemo ap*.c
     C>wcl386 -d2 -fe=apdemo ap*.c

Here we compile only those C/C++ source files that begin with the letters "ap".

In our examples, we have recompiled all the source files each time.  In general, we will only compile one of them and include the object code for the others.

Example 5:

     C>wcl -d2 -fe=apdemo aputils.c ap*.obj
     C>wcl386 -d2 -fe=apdemo aputils.c ap*.obj

The source file aputils.c is recompiled and apdemo.obj and apdata.obj are included when linking the application.  The ".obj" filename extension indicates that this file need not be compiled.

Example 6:

     C>wcl -fe=demo *.c utility.obj
     C>wcl386 -fe=demo *.c utility.obj

All of the C/C++ source files in the current directory are compiled and then linked with utility.obj to generate demo.exe. 

Example 7:

     C>set wcl=-mm -d1 -ox -k4096
     C>wcl -fe=grdemo gr*.c graph.lib -fd=grdemo

     C>set wcl386=-d1 -ox -k4096
     C>wcl386 -fe=grdemo gr*.c graph.lib -fd=grdemo

All C/C++ source files beginning with the letters "gr" are compiled and then linked with graph.lib to generate grdemo.exe which uses a 4K stack.  The temporary linker directive file that is created by WCL or WCL386 will be kept and renamed to grdemo.lnk. 

Example 8:

     C>set libos2=c:\watcom\lib286\os2;c:\os2
     C>set lib=c:\watcom\lib286\dos;c:\watcom\lib286
     C>set wcl=-mm -lp
     C>wcl grdemo1 \watcom\lib286\os2\graphp.obj phapi.lib

The file grdemo1 is compiled for the medium memory model and then linked with graphp.obj and phapi.lib to generate grdemo1.exe which is to be used with Phar Lap's 286 DOS Extender.  The "lp" option indicates that an OS/2 format executable is to be created.  The file graphp.obj in the directory "\WATCOM\LIB286\OS2" contains special initialization code for Phar Lap's 286 DOS Extender.  The file phapi.lib is part of the Phar Lap 286 DOS Extender package.  The LIBOS2 environment variable must include the location of the OS/2 libraries and the LIB environment variable must include the location of the DOS libraries (in order to locate graph.lib).   The LIBOS2 environment variable must also include the location of the OS/2 file doscalls.lib which is usually "C:\OS2".

For more complex applications, you should use the "Make" utility.

The Open Watcom C/C++ POSIX-like Compiler Driver


The Open Watcom C/C++ POSIX-like Compiler Driver is designed for generating applications, simply and quickly, using a single command line.  On the command line, you can list source file names as well as object file names.  Source files are either compiled or assembled based on file extension; object files and libraries are simply included in the link phase.  Options can be passed on to both the compiler and linker.

owcc Command Line Format


The format of the command line is:

     
     owcc [options] [files]

The square brackets [ ] denote items which are optional.

The files and options may be specified in any order.  The owcc utility uses the extension of the file name to determine if it is a source file, an object file, or a library file.  Files with extensions of "o" and "lib" are assumed to be object files and library files respectively.  Files with extensions of "asm" are assumed to be assembler source files and will be assembled by the Open Watcom Assembler.  Files with any other extension, including none at all, are assumed to be C/C++ source files and will be compiled.  Pattern matching characters ("*" and "?") may be used in the file specifications.

If no file extension is specified for a file name then the owcc utility will check for a file with one of the following extensions.

     
     Order   Name.Ext        Assumed to be
     -----   --------        ---------------
       1.    file.asm        Assembler source code
       2.    file.cxx        C++ source code
       3.    file.cpp        C++ source code
       4.    file.cc         C++ source code
       5.    file.c          C   source code

It checks for each file in the order listed.  By default, the Open Watcom Assembler will be selected to compile files with the extension "asm".  By default, the Open Watcom C++ compiler will be selected to compile files with any of the extensions "cxx", "cpp" or "cc".  By default, the Open Watcom C compiler will be selected to compile a file with a "c" extension.  The default selection of compiler can be overridden by the "-x" option, described below.

Options are prefixed with a dash (-) and may be specified in any order.  Option names were chosen to resemble those of the GNU Compiler Collection (a.k.a.  GCC).  They are translated into Open Watcom C/C++ options, or to directives for the Open Watcom C/C++ wlink utility, accordingly.  A summary of options is displayed on the screen by running the compiler driver like this:  "owcc -?".  If run without any arguments the compiler driver just displays its name and hints towards the "-?" option.

owcc Options Summary

General options:
Description:

c
compile the files only, do not link them

S
compile the source file(s), then run the Open Watcom C/C++ disassembler on the generated object file(s) instead of linking them.  Please note that this leaves you with both an object file and an assembly source file.  Unix compilers traditionally compile by generating asm source and pass that to the assembler, so there, the "-S" option is done by stopping short of assembling the file.  Open Watcom C/C++ compiles directly to object files, so we need the disassembler to achieve a similar effect.

x {c,c++}
treat all source files as written in the specified programming language, regardless of filename suffix.

o <filename>
Change the name of the generated file.  If only the preprocessor is run, this sends the preprocessed output to a file instead of the standard output stream.  If only compilation is done, this allows to change the name of the object file.   If compilation and disassembly is done, this changes the name of the assembly source file.  If owcc runs the linker, this changes the name of the generated executable or DLL.

v
operate verbosely, displaying the actual command lines used to invoke the compiler and linker, and passing flags to them to operate verbosely, too.

zq
operate quietly (default).  This is the opposite of the "-v" option.
Compiler options:
Description: 

march=i{,1,2,3}86,axp,mips,ppc
which CPU architecture instruction set is used

mtune=i{3,4,5,6}86
which x86 CPU type to optimize for

mregparm=1
use register-based argument passing conventions (default)

mregparm=0
use stack-based argument passing conventions

MMD
generate auto depend makefile fragment

MF <file>
change name of makefile style auto depend file.  Without this option, the filename is the same as the the base name of the source file, with a suffix of ".d".

MT <target>
specify target name generated in makefile style auto depend different than that of the object file name

mconsole
build target is a console application

shared
build target is a Dynamic Link Library (DLL)

mwindows
build target is a GUI application

mthreads
build target is a multi-thread environment

mrtdll
build target uses DLL version of C/C++ run-time libraries

mdefault-windowing
build target uses default windowing support

g0
(C++ only) no debugging information

g1
line number debugging information

g1+
(C only) line number debugging information plus typing information for global symbols and local structs and arrays

g2
full symbolic debugging information

g2i
(C++ only) d2 and debug inlines; emit inlines as external out-of-line functions

g2s
(C++ only) d2 and debug inlines; emit inlines as static out-of-line functions

g2t
(C++ only) full symbolic debugging information, without type names

g3
full symbolic debugging with unreferenced type names ,*

g3i
(C++ only) d3 plus debug inlines; emit inlines as external out-of-line functions

g3s
(C++ only) d3 plus debug inlines; emit inlines as static out-of-line functions

g{watcom,dwarf,codeview}
set debug output format (Open Watcom, Dwarf, Codeview)

D<name>[=text]
preprocessor #define name [text]

D+
allow extended -D macro definitions

fbrowser
generate browsing information

Wstop-after-errors=<number>
set error limit number (default is 20)

mabi={cdecl,stdcall,fastcall,pascal,fortran,syscall,watcall}
set default calling convention

fhook-epilogue
call epilogue hook routine

fmessage-full-path
use full path names in error messages

fno-short-enum
force enum base type to use at least an int

fshort-enum
force enum base type to use minimum

femit-names
emit routine name before prologue

fhook-prologue[=<number>]
call prologue hook routine with number of stack bytes available

include <file_name>
force file_name to be included in front of the source file text

fo=<file_name>
set object or preprocessor output file specification

mhard-emu-float
generate inline 80x87 instructions with emulation

msoft-float
generate calls to floating-point library

fpmath=287
generate in-line 80x87 instructions

fpmath=387
generate in-line 387 instructions

fptune=586
generate in-line 80x87 instructions optimized for Pentium processor

fptune=686
generate in-line 80x87 instructions optimized for Pentium Pro processor

fr=<file_name>
enable error file creation and specify its name

H
(C only) track include file opens

I
add directory to the list of include directories

fsigned-char
change char default from unsigned to signed

k
(C++ only) continue processing files (ignore errors)

mcmodel={f,s,m,c,l,h}
select a memory model from these choices:
f
flat

s
small

m
medium

c
compact

l
large

h
huge

t
compile code for the small memory model and then use the Open Watcom Linker to generate a "COM" file

The default is small for 16-bit and Netware, flat for 32-bit targets.

O0
turn off all optimization

O1
enable some optimazion

O2
enable most of the usual optimizations

O3
enable even more optimizations

fno-strict-aliasing
relax alias checking

fguess-branch-probability
branch prediction

fno-optimize-sibling-calls
disable call/ret optimization

finline-functions
expand functions inline

finline-limit=num
which functions to expand inline

fno-omit-frame-pointer
generate traceable stack frames

fno-omit-leaf-frame-pointer
generate more stack frames

frerun-optimizer
enable repeated optimizations

finline-intrinsics[-max]
inline intrinsic functions [-max:  more aggressively]

fschedule-prologue
control flow entry/exit seq.

floop-optimize
perform loop optimizations

funroll-loops
perform loop unrolling

finline-math
generate inline math functions

funsafe-math-optimizations
numerically unstable floating-point

ffloat-store
improve floating-point consistency

fschedule-insns
re-order instructions to avoid stalls

fkeep-duplicates
ensure unique addresses for functions

fignore-line-directives
preprocessor ignores #line directives

E
preprocess sources, sending output to standard output or filename selected via -o

C
include original comments in -E output

P
don't include #line directives in -E output

fcpp-wrap=<num>
wrap output lines at <num> columns (zero means no wrap)

ftabstop=<num>
(C++ only) set tab stop multiplier

fno-stack-check
remove stack overflow checks

fgrow-stack
generate calls to grow the stack

fstack-probe
touch stack through SS first

U <name>
preprocessor #undef name

fwrite-def
output function declarations to .def file (with typedef names)

w
turn off all warnings (same as Wlevel0)

Wall
turn on most warnings, but not all (same as Wlevel4)

Wlevel<number>
set warning level number (default is w1)

Wextra
set warning level to maximum setting

Wno-n<num>
warning control:  disable warning message <num>

Wn<num>
warning control:  enable warning message <num>

Werror
treat all warnings as errors

Woverlay
(C only) warn about problems with overlaid code

frtti
(C++ only) enable RTTI

fno-eh
(C++ only) disable exception handling (default)

feh
(C++ only) enable exception handling

feh-direct
(C++ only) enable exception handling (direct calls for destruction)

feh-table
(C++ only) enable exception handling (table-driven destructors)

std={c89,c99,ow}
select language dialect; c89 is (almost) strictly ANSI/ISO standard C89 only, c99 enables C99 support (may be incomplete), ow enables all Open Watcom C/C++ extensions.

fno-writable-strings
place literal strings in code segment

fvoid-ptr-arithmetics
(C only, Unix extension) enable arithmetic on void derived types

fwrite-def-without-typedefs
output function declarations to .def (without typedef names)

fnostdlib
suppress generation of library file names and references in object file

ffunction-sections
place each function in separate segment (near functions not allowed)

fpack-struct=[{1,2,4,8,16}]
set minimal structure packing (member alignment)

Wpadded
output warning when padding is added in a struct/class

finline-fp-rounding
inline floating point rounding code

fomit-fp-rounding
omit floating point rounding code

fnonconst-initializers
allow non-constant initializers

fsyntax-only
syntax check only

See the Open Watcom C/C++ User's Guide for a full description of compiler options.
Linker options:
Description:

b <target name>
Compile and link for the specified target system name.  See the section linker user guide for available system names.   The linker will effectively receive a -l=<target name> option.  owcc looks up <system name> in a specification table "specs.owc" to find out which of the Open Watcom C utilities to run.  One those options will be -bt=<os>, where <os> is the generic target platform name, and usually less specific than the linker <system name>.  Among the supported systems are:
286
16-bit DOS executables (synonym for "DOS") under DOS, NT and Linux
16-bit OS/2 executables (synonym for "OS2") under 32-bit OS/2 hosted OS/2 session

386
32-bit DOS executables (synonym for "DOS4G") under DOS
32-bit NT character-mode executables (synonym for "NT") under Windows NT
32-bit OS/2 executables (synonym for "OS2V2") under 32-bit OS/2 hosted OS/2 session
32-bit Linux executables (synonym for "LINUX") under Linux

CAUSEWAY
32-bit Causeway DOS Extender executables

COM
16-bit DOS "COM" files

DOS
16-bit DOS executables

DOS4G
32-bit Tenberry Software DOS/4G DOS Extender executables

DOS4GNZ
32-bit Tenberry Software DOS/4G DOS Extender non-zero base executables

NETWARE
32-bit Novell NetWare 386 NLMs

NOVELL
32-bit Novell NetWare 386 NLMs (synonym for NETWARE)

NT
32-bit Windows NT character-mode executables

NT_DLL
32-bit Windows NT DLLs

NT_WIN
32-bit Windows NT windowed executables

OS2
16-bit OS/2 V1.x executables

OS2_DLL
16-bit OS/2 DLLs

OS2_PM
16-bit OS/2 PM executables

OS2V2
32-bit OS/2 executables

OS2V2_DLL
32-bit OS/2 DLLs

OS2V2_PM
32-bit OS/2 PM executables

PHARLAP
32-bit PharLap DOS Extender executables

PMODEW
32-bit PMODE/W DOS Extender executables

QNX
16-bit QNX executables

QNX386
32-bit QNX executables

TNT
32-bit Phar Lap TNT DOS-style executable

WIN386
32-bit extended Windows 3.x executables/DLLs

WIN95
32-bit Windows 9x executables/DLLs

WINDOWS
16-bit Windows executables

WINDOWS_DLL
16-bit Windows Dynamic Link Libraries

X32R
32-bit FlashTek (register calling convention) executables

X32RV
32-bit FlashTek Virtual Memory (register calling convention) executables

X32S
32-bit FlashTek (stack calling convention) executables

X32SV
32-bit FlashTek Virtual Memory (stack calling convention) executables

These names are among the systems identified in the Open Watcom Linker initialization file, "wlsystem.lnk".   The Open Watcom Linker "SYSTEM" directives, found in this file, are used to specify default link options for particular (operating) systems.  Users can augment the Open Watcom Linker initialization file with their own system definitions and these may be specified as an argument to the "l=" option.  The "system_name" specified in the "l=" option is used to create a "SYSTEM system_name" Open Watcom Linker directive when linking the application.

L <dir>
add <dir> to directories search list for library search

l <library>
search the library named lib<library>.a

mstack-size=<size>
set stack size

fd[=<directive_file>]
keep linker directive file generated by this tool and, optionally, rename it (default name is "__owcc__.lnk").

fm[=<map_file>]
generate map file, optionally specify its name.

s
strip symbolic information not strictly required to run from executable.

Wl,"directives"
send any supplementary directives directly to the linker

Wl,@<file>
include additional linker directives from <file>.  This is actually just a special case of -Wl used to pass the linker's @ directive to pull in directives from <file>

owcc Command Line Examples


For most small applications, the owcc command will suffice.  We have only scratched the surface in describing the capabilities of the owcc command.  The following examples describe the owcc commands in more detail.

Suppose that your application is contained in three files called apdemo.c, aputils.c, and apdata.c.   We can compile and link all three files with one command.

Example 1:

     C>owcc -g apdemo.c aputils.c apdata.c

The executable program will be stored in a.out.  Each of the three files is compiled with the "g" debug option.  Debugging information is included in the executable file.

We can issue a simpler command if the current directory contains only our three C/C++ source files.

Example 2:

     C>owcc -g *.c

owcc will locate all files with the ".c" filename extension and compile each of them.  The default name of the executable file will be a.out.  Since it is only possible to have one executable with the name a.out in a directory, owcc has an option, "o", which will allow you to specify the name to be used.

Example 3:

     C>owcc -g -o apdemo *.c

By using the "o" option, the executable file will always be called apdemo.

If the directory contains other C/C++ source files which are not part of the application then other tricks may be used to identify a subset of the files to be compiled and linked.

Example 4:

     C>owcc -g -o apdemo ap*.c

Here we compile only those C/C++ source files that begin with the letters "ap".

In our examples, we have recompiled all the source files each time.  In general, we will only compile one of them and include the object code for the others.

Example 5:

     C>owcc -g -o apdemo aputils.c ap*.obj

The source file aputils.c is recompiled and apdemo.obj and apdata.obj are included when linking the application.  The ".obj" filename extension indicates that this file need not be compiled.

Example 6:

     C>owcc -o demo *.c utility.obj

All of the C/C++ source files in the current directory are compiled and then linked with utility.obj to generate demo.  The temporary linker directive file that is created by owcc will be kept and renamed to grdemo.lnk.

For more complex applications, you should use a "Make" utility.

The Open Watcom Assembler


This chapter describes the Open Watcom Assembler.  It takes as input an assembler source file (a file with extension ".asm") and produces, as output, an object file.

The Open Watcom Assembler command line syntax is the following. 

     
     WASM [options] [d:][path]filename[.ext] [options] [@env_var]

The square brackets [ ] denote items which are optional.
WASM
is the name of the Open Watcom Assembler.

d:
is an optional drive specification such as "A:", "B:", etc.  If not specified, the default drive is assumed.

path
is an optional path specification such as "\PROGRAMS\ASM\".  If not specified, the current directory is assumed.

filename
is the file name of the assembler source file to be assembled.

ext
is the file extension of the assembler source file to be assembled.  If omitted, a file extension of ".asm" is assumed.  If the period "." is specified but not the extension, the file is assumed to have no file extension.

options
is a list of valid options, each preceded by a slash ("/") or a dash ("-").  Options may be specified in any order.

The options supported by the Open Watcom Assembler are:
{0,1,2,3,4,5,6}{p}{r,s}
0
same as ".8086"

1
same as ".186"

2{p}
same as ".286" or ".286p"

3{p}
same as ".386" or ".386p" (also defines "__386__" and changes the default USE attribute of segments from "USE16" to "USE32")

4{p}
same as ".486" or ".486p" (also defines "__386__" and changes the default USE attribute of segments from "USE16" to "USE32")

5{p}
same as ".586" or ".586p" (also defines "__386__" and changes the default USE attribute of segments from "USE16" to "USE32")

6{p}
same as ".686" or ".686p" (also defines "__386__" and changes the default USE attribute of segments from "USE16" to "USE32")

p
protect mode

add r
defines "__REGISTER__"

add s
defines "__STACK__"

Example:

     -2      -3p     -4pr    -5p

bt=<os>
defines "__<os>__" and checks the "<os>_INCLUDE" environment variable for include files

c
do not output OMF COMENT records that allow WDISASM to figure out when data bytes have been placed in a code segment

d<name>[=text]
define text macro

d1
line number debugging support

e
stop reading assembler source file at END directive.  Normally, anything following the END directive will cause an error.

e<number>
set error limit number

fe=<file_name>
set error file name

fo=<file_name>
set object file name

fi=<file_name>
force <file_name> to be included

fpc
same as ".no87"

fpi
inline 80x87 instructions with emulation

fpi87
inline 80x87 instructions

fp0
same as ".8087"

fp2
same as ".287" or ".287p"

fp3
same as ".387" or ".387p"

fp5
same as ".587" or ".587p"

fp6
same as ".687" or ".687p"

i=<directory>
add directory to list of include directories
Note:  to be host platform independent the form like i="../h" (quoted path and forward slash separator) is recommended.

j or s
force signed types to be used for signed values

m{t,s,m,c,l,h,f}
memory model:  (Tiny, Small, Medium, Compact, Large, Huge, Flat)
-mt
Same as ".model tiny"

-ms
Same as ".model small"

-mm
Same as ".model medium"

-mc
Same as ".model compact"

-ml
Same as ".model large"

-mh
Same as ".model huge"

-mf
Same as ".model flat"

Each of the model directives also defines "__<model>__" (e.g., ".model small" defines "__SMALL__").   They also affect whether something like "foo proc" is considered a "far" or "near" procedure.

nd=<name>
set data segment name

nm=<name>
set module name

nt=<name>
set name of text segment

o
allow C form of octal constants

zcm=<mode>
set compatibility mode to <mode>
Values
Description

watcom (default)
Open Watcom WASM mode

masm
Microsoft MASM mode

tasm
Borland TASM mode

ideal
Borland TASM IDEAL mode

not specified
MASM mode is used

zld
remove file dependency information

zq or q
operate quietly

zz
remove "@size" from STDCALL function names

zzo
don't mangle STDCALL symbols (WASM backward compatible)

?  or h
print this message

w<number>
set warning level number

we
treat all warnings as errors

wx
set warning level to maximum setting

Assembler Directives, Operators and Assembly Opcodes


It is not the intention of this chapter to describe assembly-language programming in any detail.  You should consult a book that deals with this topic.  However, we present an alphabetically ordered list of the directives, opcodes and register names that are recognized by the assembler.

.186           .286            .286c          .286p           .287           .386            .386p          .387            .486           .486p           .586           .586p           .686           .686p           .8086          .8087           addr           alias           align          .alpha          and            assume          .break         byte           casemap        catstr         .code           comm           comment         .const         .continue       .cref          .data          .data?         db              dd             df              .dosseg        dosseg          dp             dq              dt             dup             dw              dword          echo            .else          else            elseif         end             .endif         endif           endm           endp            ends           .endw           eq             equ             equ2           .err            .errb          .errdef         .errdif        .errdifi       .erre          .erridn        .erridni        .errnb         .errndef        .errnz         even           .exit          exitm          extern          externdef      extrn           far            .fardata        .fardata?      for             forc           fword           ge             global          group          gt              high           highword        .if            if              if1            if2             ifb            ifdef          ifdif          ifdifi          ife            ifidn           ifidni         ifnb            ifndef         include         includelib     invoke         irp             irpc            .k3d           label           le             length          lengthof       .lfcond        .list           .listall       .listif         .listmacro     .listmacroall  local           low            lowword        lroffset       lt             macro           mask           .mmx            mod             .model         name           ne             near            .no87          .nocref         .nolist      
offset         opattr         option          org            oword           page           popcontext      proc           proto           ptr            public          purge          pushcontext    pword           qword          .radix          record         .repeat         repeat         .sall           sbyte          sdword          seg            segment         .seq           .sfcond        size           sizeof         .stack          .startup       struc           struct         subtitle        subttl         sword          tbyte          textequ        .tfcond         this           title           typedef        union           .until         uses            .while         width           word           .xcref          .xlist         .xmm           .xmm2          .xmm3        

aaa            aad             aam            aas             adc            add             addpd          addps          addsd          addss           addsubpd       addsubps        and            andnpd          andnps         andpd           andps          arpl            bound          bp              bsf            bsr             bswap          bt              btc            btr            bts             call           callf           cbw            cdq             clc            cld             clflush        cli             clts           cmc             cmova          cmovae          cmovb          cmovbe          cmovc          cmove           cmovg          cmovge          cmovl          cmovle          cmovna         cmovnae         cmovnb         cmovnbe        cmovnc          cmovne         cmovng          cmovnge        cmovnl          cmovnle        cmovno         cmovnp          cmovns         cmovnz          cmovo          cmovp           cmovpe         cmovpo          cmovs          cmovz           cmp            cmpeqpd         cmpeqps        cmpeqsd        cmpeqss         cmplepd        cmpleps         cmplesd        cmpless        cmpltpd         cmpltps        cmpltsd         cmpltss        cmpneqpd       cmpneqps        cmpneqsd       cmpneqss       cmpnlepd        cmpnleps       cmpnlesd       cmpnless       cmpnltpd       cmpnltps        cmpnltsd       cmpnltss       cmpordpd        cmpordps       cmpordsd       cmpordss        cmppd          cmpps           cmps           cmpsb           cmpsd          cmpss           cmpsw          cmpunordpd     cmpunordps      cmpunordsd     cmpunordss     cmpxchg         cmpxchg8b      comisd         comiss          cpuid          cvtdq2pd        cvtdq2ps       cvtpd2dq       cvtpd2pi        cvtpd2ps       cvtpi2pd       cvtpi2ps       cvtps2dq       cvtps2pd        cvtps2pi       cvtsd2si       cvtsd2ss        cvtsi2sd       cvtsi2ss       cvtss2sd        cvtss2si       cvttpd2dq      cvttpd2pi      cvttps2dq      cvttps2pi      cvttsd2si     
cvttss2si      cwd            cwde            daa             das            dec             div            divpd           divps          divsd           divss          emms            enter          f2xm1           fabs           fadd            faddp          fbld            fbstp          fchs            fclex          fcmovb          fcmovbe        fcmove         fcmovnb        fcmovnbe       fcmovne         fcmovnu        fcmovu          fcom           fcomi           fcomip         fcomp          fcompp         fcos           fdecstp         fdisi          fdiv            fdivp          fdivr           fdivrp         femms           feni           ffree           fiadd          ficom           ficomp         fidiv           fidivr         fild            fimul          fincstp        finit          fist           fistp          fisttp         fisub           fisubr         flat            fld            fld1            fldcw          fldenv          fldenvd        fldenvw         fldl2e         fldl2t          fldlg2         fldln2         fldpi          fldz           fmul           fmulp          fnclex         fndisi         fneni           fninit         fnop            fnrstor        fnrstord        fnrstorw       fnsave         fnsaved         fnsavew        fnstcw          fnstenv        fnstenvd       fnstenvw        fnstsw         fpatan          fprem          fprem1          fptan          frndint         frstor         frstord        frstorw         fsave          fsaved          fsavew         fscale          fsetpm         fsin            fsincos        fsqrt          fst            fstcw           fstenv         fstenvd        fstenvw         fstp           fstsw           fsub           fsubp           fsubr          fsubrp          ftst           fucom           fucomi         fucomip         fucomp         fucompp        fwait           fxam           fxch            fxrstor        fxsave          fxtract        fyl2x           fyl2xp1        haddpd          haddps         hlt           
hsubpd         hsubps         idiv            imul           in             inc             ins            insb            insd           insw            int            into            invd           invlpg          iret           iretd           iretdf         iretf           ja             jae             jb              jbe            jc              jcxz           je              jecxz          jg              jge             jl             jle             jmp            jmpf            jna            jnae           jnb             jnbe           jnc             jne            jng             jnge           jnl             jnle           jno             jnp             jns            jnz             jo             jp              jpe            jpo            js              jz             lahf            lar            lddqu           ldmxcsr        lds             lea            leave           les            lfence          lfs            lgdt            lgs             lidt           lldt            lmsw           lock            lods           lodsb           lodsd          lodsw           loop           loopd           loope          looped          loopew         loopne         loopned         loopnew        loopnz          loopnzd        loopnzw        loopw          loopz          loopzd          loopzw         lsl             lss            ltr             maskmovdqu     maskmovq        maxpd          maxps           maxsd          maxss           mfence         minpd           minps          minsd          minss          monitor        mov             movapd         movaps          movd           movddup         movdq2q        movdqa          movdqu         movhlps        movhpd         movhps         movlhps         movlpd         movlps          movmskpd       movmskps       movntdq         movnti         movntpd         movntps        movntq          movq           movq2dq        movs           movsb          movsd          movshdup       movsldup        movss          movsw           movsx        
movupd         movups         movzx           mul            mulpd          mulps          mulsd           mulss          mwait           near           neg             nop             not            or              orpd           orps            out            outs            outsb          outsd           outsw          packssdw        packsswb       packuswb       paddb           paddd          paddq           paddsb         paddsw          paddusb        paddusw         paddw          pand            pandn          pause          pavgb          pavgusb        pavgw           pcmpeqb        pcmpeqd         pcmpeqw        pcmpgtb        pcmpgtd        pcmpgtw        pextrw          pf2id          pf2iw           pfacc          pfadd           pfcmpeq        pfcmpge        pfcmpgt         pfmax          pfmin           pfmul          pfnacc          pfpnacc        pfrcp           pfrcpit1       pfrcpit2       pfrsqit1        pfrsqrt        pfsub           pfsubr         pi2fd           pi2fw          pinsrw          pmaddwd        pmaxsw         pmaxub          pminsw         pminub          pmovmskb       pmulhrw        pmulhuw        pmulhw         pmullw          pmuludq        pop             popa           popad           popf           popfd           por            prefetch        prefetchnta    prefetcht0     prefetcht1     prefetcht2     prefetchw      psadbw          pshufd         pshufhw        pshuflw         pshufw         pslld           pslldq         psllq           psllw          psrad           psraw          psrld           psrldq         psrlq           psrlw          psubb          psubd          psubq          psubsb          psubsw         psubusb         psubusw        psubw           pswapd         punpckhbw      punpckhdq       punpckhqdq     punpckhwd      punpcklbw       punpckldq      punpcklqdq     punpcklwd       push           pusha           pushad         pushd           pushf          pushfd          pushw          pxor            rcl            rcpps           rcpss        
rcr            rdmsr           rdpmc          rdtsc           rep            repe            repne          repnz           rept           repz            ret            retd            retf           retfd           retn           rol             ror            rsm             rsqrtps        rsqrtss         sahf           sal             sar            sbb             scas            scasb          scasd          scasw          seta           setae          setb           setbe          setc           sete           setg            setge          setl            setle          setna          setnae         setnb          setnbe          setnc          setne           setng          setnge          setnl          setnle          setno          setnp           setns          setnz           seto           setp            setpe          setpo           sets           setz            sfence         sgdt            shl            shld            short          shr             shrd           shufpd          shufps         sidt            sldt           smsw            sp             sqrtpd          sqrtps         sqrtsd          sqrtss         stc             std            sti             stmxcsr        stos            stosb          stosd           stosw          str             sub            subpd           subps          subsd           subss          sysenter        sysexit        test            ucomisd        ucomiss        unpckhpd        unpckhps       unpcklpd       unpcklps       verr           verw            wait           wbinvd          wrmsr          xadd            xchg           xlat            xlatb          xor             xorpd          xorps         

ah             al              ax             bh              bl              bx             ch              cl             cr0             cr2             cr3            cr4             cs             cx              dh             di             dl              dr0            dr1             dr2            dr3             dr6             dr7            ds              dx             eax             ebp            ebx            ecx             edi            edx             es             esi             esp             fs             gs              mm0            mm1             mm2            mm3             mm4             mm5            mm6             mm7            si              ss              st             st0             st1            st2             st3            st4             st5             st6            st7             tr3            tr4             tr5            tr6             tr7             xmm0           xmm1            xmm2           xmm3            xmm4           xmm5            xmm6           xmm7          

Unsupported Directives


Other assemblers support directives that this assembler does not.  The following is a list of directives that are ignored by the Open Watcom Assembler (use of these directives results in a warning message). 

     
     .alpha         .cref           .lfcond        .list
     .listall       .listif         .listmacro     .listmacroall
     .nocref        .nolist         page           .sall
     .seq           .sfcond         subtitle       subttl
     .tfcond        title           .xcref         .xlist

The following is a list of directives that are flagged by the Open Watcom Assembler (use of these directives results in an error message). 

     
     addr           .break          casemap        catstr
     .continue      echo            .else          endmacro
     .endif         .endw           .exit          high
     highword       .if             invoke         low
     lowword        lroffset        mask           opattr
     option         popcontext     proto          purge
     pushcontext    .radix         record          .repeat
     .startup       this            typedef        union
     .until         .while          width

Open Watcom Assembler Specific


There are a few specific features in Open Watcom Assembler

Naming convention


     
                       Procedure   Variable
     Convention         Name         Name
     ---------------  ----------  ---------
     C                   '_*'        '_*'
     WATCOM_C         see section Open Watcom "C" name mangler
     SYSCALL             '*'          '*'
     STDCALL           '_*@nn'       '_*'
     STDCALL            '_*'         '_*'    see note 1
     STDCALL             '*'          '*'    see note 2
     BASIC               '^'         '^'
     FORTRAN             '^'          '^'
     PASCAL              '^'          '^'

Notes:
  1. In STDCALL procedures name 'nn' is overall parametrs size in bytes.  '@nn' is suppressed when -zz command line option is used (WATCOM 10.0 compatibility).
  2. STDCALL symbols mangling is suppressed by -zzo command line option (WASM backward compatible).

Open Watcom "C" name mangler


     
     Command line     Procedure   Variable
       option           Name         Name
     ---------------  ----------  ---------
     0,1,2              '*_'         '_*'
     3,4,5,6 with r     '*_'        '_*'
     3,4,5,6 with s      '*'        '*'

Calling convention


     
                            Parameters    Parameters   Cleanup caller
     Convention   Vararg    passed by       order         stack
     -----------  ------  ------------  ------------- --------------
     C             yes       stack       right to left    no
     WATCOM_C      yes      registers    right to left    see note 1
                   yes       stack       right to left    no
     SYSCALL       yes      stack        right to left    no
     STDCALL       yes      stack        right to left    yes see note 2
     BASIC         no       stack       left to right    yes
     FORTRAN       no       stack        left to right    yes
     PASCAL        no       stack        left to right    yes

Notes:
  1. If any parameter is passed on the stack then WASM automaticaly cleanup caller stack.
  2. For STDCALL procedures WASM automaticaly cleanup caller stack, except case when vararg parameter is used.

Open Watcom Assembler Diagnostic Messages

1
Size doesn't match with previous definition

2
Invalid instruction with current CPU setting

3
LOCK prefix is not allowed on this instruction

4
REP prefix is not allowed on this instruction

5
Invalid memory pointer

6
Cannot use 386 addressing mode with current CPU setting

7
Too many base registers

8
Invalid index register

9
Scale factor must be 1, 2, 4 or 8

10
invalid addressing mode with current CPU setting

11
ESP cannot be used as index

12
Too many base/index registers

13
Memory offset cannot reference to more than one label

14
Offset must be relocatable

15
Memory offset expected

16
Invalid indirect memory operand

17
Cannot mix 16 and 32-bit registers

18
CPU type already set

19
Unknown directive

20
Expecting comma

21
Expecting number

22
Invalid label definition

23
Invalid use of SHORT, NEAR, FAR operator

24
No memory

25
Cannot use 386 segment register with current CPU setting

26
POP CS is not allowed

27
Cannot use 386 register with current CPU setting

28
Only MOV can use special register

29
Cannot use TR3, TR4, TR5 in current CPU setting

30
Cannot use SHORT with CALL

31
Only SHORT displacement is allowed

32
Syntax error

33
Prefix must be followed by an instruction

34
No size given before 'PTR' operator

35
Invalid IMUL format

36
Invalid SHLD/SHRD format

37
Too many commas

38
Syntax error:  Unexpected colon

39
Operands must be the same size

40
Invalid instruction operands

41
Immediate constant too large

42
Can not use short or near modifiers with this instruction

43
Jump out of range

44
Displacement cannot be larger than 32k

45
Initializer value too large

46
Symbol already defined

47
Immediate data too large

48
Immediate data out of range

49
Can not transfer control to stack symbol

50
Offset cannot be smaller than WORD size

51
Can not take offset of stack symbol

52
Can not take segment of stack symbol

53
Segment too large

54
Offset cannot be larger than 32k

55
Operand 2 too big

56
Operand 1 too small

57
Too many arithmetic operators

58
Too many open square brackets

59
Too many close square brackets

60
Too many open brackets

61
Too many close brackets

62
Invalid number digit

63
Assembler Code is too long

64
Brackets are not balanced

65
Operator is expected

66
Operand is expected

67
Too many tokens in a line

68
Bracket is expected

69
Illegal use of register

70
Illegal use of label

71
Invalid operand in addition

72
Invalid operand in subtraction

73
One operand must be constant

74
Constant operand is expected

75
A constant operand is expected in addition

76
A constant operand is expected in subtraction

77
A constant operand is expected in multiplication

78
A constant operand is expected in division

79
A constant operand is expected after a positive sign

80
A constant operand is expected after a negative sign

81
Label is not defined

82
More than one override

83
Label is expected

84
Only segment or group label is allowed

85
Only register or label is expected in override

86
Unexpected end of file

87
Label is too long

88
This feature has not been implemented yet

89
Internal Error #1

90
Can not take offset of group

91
Can not take offset of segment

92
Invalid character found

93
Invalid operand size for instruction

94
This instruction is not supported

95
size not specified -- BYTE PTR is assumed

96
size not specified -- WORD PTR is assumed

97
size not specified -- DWORD PTR is assumed

500
Segment parameter is defined already

501
Model parameter is defined already

502
Syntax error in segment definition

503
'AT' is not supported in segment definition

504
Segment definition is changed

505
Lname is too long

506
Block nesting error

507
Ends a segment which is not opened

508
Segment option is undefined

509
Model option is undefined

510
No segment is currently opened

511
Lname is used already

512
Segment is not defined

513
Public is not defined

514
Colon is expected

515
A token is expected after colon

516
Invalid qualified type

517
Qualified type is expected

518
External definition different from previous one

519
Memory model is not found in .MODEL

520
Cannot open include file

521
Name is used already

522
Library name is missing

523
Segment name is missing

524
Group name is missing

525
Data emitted with no segment

526
Seglocation is expected

527
Invalid register

528
Cannot address with assumed register

529
Invalid start address

530
Label is already defined

531
Token is too long

532
The line is too long after expansion

533
A label is expected after colon

534
Must be associated with code

535
Procedure must have a name

536
Procedure is alreadly defined

537
Language type must be specified

538
End of procedure is not found

539
Local variable must immediately follow PROC or MACRO statement

540
Extra character found

541
Cannot nest procedures

542
No procedure is currently defined

543
Procedure name does not match

544
Vararg requires C calling convention

545
Model declared already

546
Model is not declared

547
Backquote expected

548
COMMENT delimiter expected

549
End directive required at end of file

550
Nesting level too deep

551
Symbol not defined

552
Insert Stupid warning #1 here

553
Insert Stupid warning #2 here

554
Spaces not allowed in command line options

555
Error:

556
Source File

557
No filename specified.

558
Out of Memory

559
Cannot Open File -

560
Cannot Close File -

561
Cannot Get Start of Source File -

562
Cannot Set to Start of Source File -

563
Command Line Contains More Than 1 File To Assemble

564
include path %s.

565
Unknown option %s.  Use -?  for list of options.

566
read more command line from %s.

567
Internal error in %s(%u)

568
OBJECT WRITE ERROR !!

569
NO LOR PHARLAP !!

570
Parameter Required

571
Expecting closing square bracket

572
Expecting file name

573
Floating point instruction not allowed with -fpc

574
Too many errors

575
Build target not recognised

576
Public constants should be numeric

577
Expecting symbol

578
Do not mix simplified and full segment definitions

579
Parms passed in multiple registers must be accessed separately, use %s

580
Ten byte variables not supported in register calling convention

581
Parameter type not recognised

582
forced error:

583
forced error:  Value not equal to 0 :  %d

584
forced error:  Value equal to 0:  %d

585
forced error:  symbol defined:  %s

586
forced error:  symbol not defined:  %s

587
forced error:  string blank :  <%s>

588
forced error:  string not blank :  <%s>

589
forced error:  strings not equal :  <%s> :  <%s>

590
forced error:  strings equal :  <%s> :  <%s>

591
included by file %s(%d)

592
macro called from file %s(%d)

593
Symbol %s not defined

594
Extending jump

595
Ignoring inapplicable directive

596
Unknown symbol class '%s'

597
Symbol class for '%s' already established

598
number must be a power of 2

599
alignment request greater than segment alignment

600
'%s' is already defined

601
%u unclosed conditional directive(s) detected

The Open Watcom Library Manager


The Open Watcom Library Manager can be used to create and update object library files.  It takes as input an object file or a library file and creates or updates a library file.  For OS/2, Win16 and Win32 applications, it can also create import libraries from Dynamic Link Libraries. 

An object library is essentially a collection of object files.  These object files generally contain utility routines that can be used as input to the Open Watcom Linker to create an application.  The following are some of the advantages of using library files.
  1. Only those modules that are referenced will be included in the executable file.  This eliminates the need to know which object files should be included and which ones should be left out when linking an application.
  2. Libraries are a good way of organizing object files.  When linking an application, you need only list one library file instead of several object files.

The Open Watcom Library Manager currently runs under the following operating systems.

The Open Watcom Library Manager Command Line


The following describes the Open Watcom Library Manager command line. 

     
     WLIB [options_1] lib_file [options_2] [cmd_list]

The square brackets "[]" denote items which are optional.
lib_file
is the file specification for the library file to be processed.  If no file extension is specified, a file extension of "lib" is assumed.

options_1
is a list of valid options.  Options may be specified in any order.  If you are using a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager, options are preceded by a "/" or "-" character.  If you are using a UNIX-hosted version of the Open Watcom Library Manager, options are preceded by a "-" character.

options_2
is a list of valid options.  These options are only permitted if you are running a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager and must be preceded by a "/" character.  The "-" character cannot be used as an option delimiter for options following the library file name since it will be interpreted as a delete command.

cmd_list
is a list of commands to the Open Watcom Library Manager specifying what operations are to be performed.  Each command in cmd_list is separated by a space.

The following is a summary of valid options.  Items enclosed in square brackets "[]" are optional.   Items separated by an or-bar "|" and enclosed in parentheses "()" indicate that one of the items must be specified.  Items enclosed in angle brackets "<>" are to be replaced with a user-supplied name or value (the "<>" are not included in what you specify).
?
display the usage message

b
suppress creation of backup file

c
perform case sensitive comparison

d=<output_directory>
directory in which extracted object modules will be placed

fa
output AR format library (host default ar format)

fab
output AR format library (BSD ar format)

fac
output AR format library (COFF ar format)

fag
output AR format library (GNU ar format)

fm
output MLIB format library

fo
output OMF format library

h
display the usage message

ia
generate AXP import records

ii
generate X86 import records

ip
generate PPC import records

ie
generate ELF import records

ic
generate COFF import records

io
generate OMF import records

i(r|n)(n|o)
imports for the resident/non-resident names table are to be imported by name/ordinal.

l[=<list_file>]
create a listing file

m
display C++ mangled names

n
always create a new library

o=<output_file>
set output file name for library

p=<record_size>
set library page size (supported for "OMF" library format only)

pa
set optimal library page size automaticaly (supported for "OMF" library format only)

q
suppress identification banner

s
strip line number records from object files (supported for "OMF" library format only)

t
remove path information from module name specified in THEADR records (supported for "OMF" library format only)

v
do not suppress identification banner

x
extract all object modules from library

zld
strip file dependency info from object files (supported for "OMF" library format only)

The following sections describe the operations that can be performed on a library file.  Note that before making a change to a library file, the Open Watcom Library Manager makes a backup copy of the original library file unless the "o" option is used to specify an output library file whose name is different than the original library file, or the "b" option is used to suppress the creation of the backup file.  The backup copy has the same file name as the original library file but has a file extension of "bak".  Hence, lib_file should not have a file extension of "bak". 

Open Watcom Library Manager Module Commands


The following is a summary of basic Open Watcom Library Manager module manipulation commands:
+
add module to a library

-
remove module from a library

* or :
extract module from a library ( :  is used with a UNIX-hosted version of the Open Watcom Library Manager, otherwise * is used)

++
add import library entry

Adding Modules to a Library File


An object file can be added to a library file by specifying a +obj_file command where obj_file is the file specification for an object file.  If you are using a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager, a file extension of "obj" is assumed if none is specified.  If you are using a UNIX-hosted version of the Open Watcom Library Manager, a file extension of "o" is assumed if none is specified.  If the library file does not exist, a warning message will be issued and the library file will be created.

Example:

     wlib mylib +myobj

In the above example, the object file "myobj" is added to the library file "mylib.lib".

When a module is added to a library, the Open Watcom Library Manager will issue a warning if a symbol redefinition occurs.  This will occur if a symbol in the module being added is already defined in another module that already exists in the library file.  Note that the module will be added to the library in any case.

It is also possible to combine two library files together.  The following example adds all modules in the library "newlib.lib" to the library "mylib.lib".

Example:

     wlib mylib +newlib.lib

Note that you must specify the "lib" file extension.  Otherwise, the Open Watcom Library Manager will assume you are adding an object file.

Deleting Modules from a Library File


A module can be deleted from a library file by specifying a -mod_name command where mod_name is the file name of the object file when it was added to the library with the directory and file extension removed.

Example:

     wlib mylib -myobj

In the above example, the Open Watcom Library Manager is instructed to delete the module "myobj" from the library file "mylib.lib".

It is also possible to specify a library file instead of a module name.

Example:

     wlib mylib -oldlib.lib

In the above example, all modules in the library file "oldlib.lib" are removed from the library file "mylib.lib".   Note that you must specify the "lib" file extension.  Otherwise, the Open Watcom Library Manager will assume you are removing an object module.

Replacing Modules in a Library File


A module can be replaced by specifying a -+mod_name or +-mod_name command.  The module mod_name is deleted from the library.  The object file "mod_name" is then added to the library.

Example:

     wlib mylib -+myobj

In the above example, the module "myobj" is replaced by the object file "myobj".

It is also possible to merge two library files.

Example:

     wlib mylib -+updlib.lib

In the above example, all modules in the library file "updlib.lib" replace the corresponding modules in the library file "mylib.lib".  Any module in the library "updlib.lib" not in library "mylib.lib" is added to the library "mylib.lib".  Note that you must specify the "lib" file extension.  Otherwise, the Open Watcom Library Manager will assume you are replacing an object module.

Extracting a Module from a Library File


A module can be extracted from a library file by specifying a *mod_name [=file_name] command for a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager or a :mod_name [=file_name] command for a UNIX-hosted version of the Open Watcom Library Manager.  The module mod_name is not deleted but is copied to a disk file.  If mod_name is preceded by a path specification, the output file will be placed in the directory identified by the path specification.  If mod_name is followed by a file extension, the output file will contain the specified file extension.

Example:

     wlib mylib *myobj        DOS, OS/2 or Windows-hosted
         or
     wlib mylib :myobj        UNIX-hosted

In the above example, the module "myobj" is copied to a disk file.  The disk file will be an object file with file name "myobj".  If you are running a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager, a file extension of "obj" will be used.  If you are running a UNIX-hosted version of the Open Watcom Library Manager, a file extension of "o" will be used.

Example:

     wlib mylib *myobj.out    DOS, OS/2 or Windows-hosted
         or
     wlib mylib :myobj.out    UNIX-hosted

In the above example, the module "myobj" will be extracted from the library file "mylib.lib" and placed in the file "myobj.out"

The following form of the extract command can be used if the module name is not the same as the output file name.

Example:

     wlib mylib *myobj=newmyobj.out    DOS, OS/2 or Windows-hosted
         or
     wlib mylib :myobj=newmyobj.out    UNIX-hosted

You can extract a module from a file and have that module deleted from the library file by specifying a *-mod_name command for a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager or a :-mod_name command for a UNIX-hosted version of the Open Watcom Library Manager.  The following example performs the same operations as in the previous example but, in addition, the module is deleted from the library file.

Example:

     wlib mylib *-myobj.out   DOS, OS/2 or Windows-hosted
         or
     wlib mylib :-myobj.out   UNIX-hosted

Note that the same result is achieved if the delete operator precedes the extract operator.

Creating Import Libraries


The Open Watcom Library Manager can also be used to create import libraries from Dynamic Link Libraries.  Import libraries are used when linking OS/2, Win16 or Win32 applications.

Example:

     wlib implib +dynamic.dll

In the above example, the following actions are performed.  For each external symbol in the specified Dynamic Link Library, a special object module is created that identifies the external symbol and the actual name of the Dynamic Link Library it is defined in.  This object module is then added to the specified library.  The resulting library is called an import library.

Note that you must specify the "dll" file extension.  Otherwise, the Open Watcom Library Manager will assume you are adding an object file.

Creating Import Library Entries


An import library entry can be created and added to a library by specifying a command of the following form.

     
     ++sym.dll_name[.[altsym].export_name][.ordinal]
where
description

sym
is the name of a symbol in a Dynamic Link Library.

dll_name
is the name of the Dynamic Link Library that defines sym.

altsym
is the name of a symbol in a Dynamic Link Library.  When omitted, the default symbol name is sym.

export_name
is the name that an application that is linking to the Dynamic Link Library uses to reference sym.  When omitted, the default export name is sym.

ordinal
is the ordinal value that can be used to identify sym instead of using the name export_name.

Example:

     wlib math ++__sin.trig.sin.1

In the above example, an import library entry will be created for symbol sin and added to the library "math.lib".   The symbol sin is defined in the Dynamic Link Library called "trig.dll" as __sin.  When an application is linked with the library "math.lib", the resulting executable file will contain an import by ordinal value 1.  If the ordinal value was omitted, the resulting executable file would contain an import by name sin.

Commands from a File or Environment Variable


The Open Watcom Library Manager can be instructed to process all commands in a disk file or environment variable by specifying the @name command where name is a file specification for the command file or the name of an environment variable.   A file extension of "lbc" is assumed for files if none is specified.  The commands must be one of those previously described.

Example:

     wlib mylib @mycmd

In the above example, all commands in the environment variable "mycmd" or file "mycmd.lbc" are processed by the Open Watcom Library Manager.

Open Watcom Library Manager Options


The following sections describe the list of options allowed when invoking the Open Watcom Library Manager.

Suppress Creation of Backup File - "b" Option


The "b" option tells the Open Watcom Library Manager to not create a backup library file.  In the following example, the object file identified by "new" will be added to the library file "mylib.lib".

Example:

     wlib -b mylib +new

If the library file "mylib.lib" already exits, no backup library file ("mylib.bak") will be created.

Case Sensitive Symbol Names - "c" Option


The "c" option tells the Open Watcom Library Manager to use a case sensitive compare when comparing a symbol to be added to the library to a symbol already in the library file.  This will cause the names "myrtn" and "MYRTN" to be treated as different symbols.  By default, comparisons are case insensitive.  That is the symbol "myrtn" is the same as the symbol "MYRTN".

Specify Output Directory - "d" Option


The "d" option tells the Open Watcom Library Manager the directory in which all extracted modules are to be placed.  The default is to place all extracted modules in the current directory.

In the following example, the module "mymod" is extracted from the library "mylib.lib".  If you are running a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager, the module will be placed in the file "\obj\mymod.obj".  If you are running a UNIX-hosted version of the Open Watcom Library Manager, the module will be placed in the file "/o/mymod.o".

Example:

     wlib -d=\obj mymod       DOS, OS/2 or Windows-hosted
         or
     wlib -d=/o mymod         UNIX-hosted

Specify Output Format - "f" Option


The "f" option tells the Open Watcom Library Manager the format of the output library.  The default output format is determined by the type of object files that are added to the library when it is created.  The possible output format options are:
fa
output AR format library, host OS default ar format

fab
output AR format library, BSD ar format

fac
output AR format library, COFF ar format

fag
output AR format library, GNU ar format

fm
output MLIB format library

fo
output OMF format library

Generating Imports - "i" Option


The "i" option can be used to describe type of import library to create.
ia
generate AXP import records

ii
generate X86 import records

ip
generate PPC import records

ie
generate ELF import records

ic
generate COFF import records

io
generate OMF import records

When creating import libraries from Dynamic Link Libraries, import entries for the names in the resident and non-resident names tables are created.  The "i" option can be used to describe the method used to import these names.
iro
Specifying "iro" causes imports for names in the resident names table to be imported by ordinal.

irn
Specifying "irn" causes imports for names in the resident names table to be imported by name.  This is the default.

ino
Specifying "ino" causes imports for names in the non-resident names table to be imported by ordinal.  This is the default.

inn
Specifying "inn" causes imports for names in the non-resident names table to be imported by name.

Example:

     wlib -iro -inn implib +dynamic.dll

Note that you must specify the "dll" file extension for the Dynamic Link Library.  Otherwise an object file will be assumed.

Creating a Listing File - "l" Option


The "l" (lower case "L") option instructs the Open Watcom Library Manager to produce a list of the names of all symbols that can be found in the library file to a listing file.  The file name of the listing file is the same as the file name of the library file.  The file extension of the listing file is "lst".

Example:

     wlib -l mylib

In the above example, the Open Watcom Library Manager is instructed to list the contents of the library file "mylib.lib" and produce the output to a listing file called "mylib.lst".

An alternate form of this option is -l=list_file.  With this form, you can specify the name of the listing file.  When specifying a listing file name, a file extension of "lst" is assumed if none is specified.

Example:

     wlib -l=mylib.out mylib

In the above example, the Open Watcom Library Manager is instructed to list the contents of the library file "mylib.lib" and produce the output to a listing file called "mylib.out".

You can get a listing of the contents of a library file to the terminal by specifying only the library name on the command line as demonstrated by the following example.

Example:

     wlib mylib

Display C++ Mangled Names - "m" Option


The "m" option instructs the Open Watcom Library Manager to display C++ mangled names rather than displaying their demangled form.  The default is to interpret mangled C++ names and display them in a somewhat more intelligible form.

Always Create a New Library - "n" Option


The "n" option tells the Open Watcom Library Manager to always create a new library file.  If the library file already exists, a backup copy is made (unless the "b" option was specified).  The original contents of the library are discarded and a new library is created.  If the "n" option was not specified, the existing library would be updated.

Example:

     wlib -n mylib +myobj

In the above example, a library file called "mylib.lib" is created.  It will contain a single object module, namely "myobj", regardless of the contents of "mylib.lib" prior to issuing the above command.   If "mylib.lib" already exists, it will be renamed to "mylib.bak".

Specifying an Output File Name - "o" Option


The "o" option can be used to specify the output library file name if you want the original library to remain unchanged and a new library created.

Example:

     wlib -o=newlib lib1 +lib2.lib

In the above example, the modules from "lib1.lib" and "lib2.lib" are added to the library "newlib.lib".   Note that since the original library remains unchanged, no backup copy is created.  Also, if the "l" option is used to specify a listing file, the listing file will assume the file name of the output library.

Specifying a Library Record Size - "p" and "pa" Options


The "p" option specifies the record size in bytes for each record in the library file.  The record size must be a power of 2 and in the range 16 to 32768.  If the record size is less than 16, it will be rounded up to 16.   If the record size is greater than 16 and not a power of 2, it will be rounded up to the nearest power of 2.  The default record size is 256 bytes.

Each entry in the dictionary of a library file contains an offset from the start of the file which points to a module.   The offset is 16 bits and is a multiple of the record size.  Since the default record size is 256, the maximum size of a library file for a record size of 256 is 256*64K.  If the size of the library file increases beyond this size, you must increase the record size.

Example:

     wlib -p=512 lib1 +lib2.lib

In the above example, the Open Watcom Library Manager is instructed to create/update the library file "lib1.lib" by adding the modules from the library file "lib2.lib".  The record size of the resulting library file is 512 bytes.

The "pa" option specifies the record size is determined automaticaly to be minimal in size.

Example:

     wlib -pa lib1 +lib2.lib

In the above example, the Open Watcom Library Manager is instructed to create/update the library file "lib1.lib" by adding the modules from the library file "lib2.lib".  The record size of the resulting library file is optimal (minimal) regardles of what each library page size is.

Operate Quietly - "q" Option


The "q" option suppressing the banner and copyright notice that is normally displayed when the Open Watcom Library Manager is invoked.

Example:

     wlib -q -l mylib

Strip Line Number Records - "s" Option


The "s" option tells the Open Watcom Library Manager to remove line number records from object files that are being added to a library.  Line number records are generated in the object file if the "d1" option is specified when compiling the source code.

Example:

     wlib -s mylib +myobj

Trim Module Name - "t" Option


The "t" option tells the Open Watcom Library Manager to remove path information from the module name specified in THEADR records in object files that are being added to a library.  The module name is created from the file name by the compiler and placed in the THEADR record of the object file.  The module name will contain path information if the file name given to the compiler contains path information.

Example:

     wlib -t mylib +myobj

Operate Verbosely - "v" Option


The "v" option enables the display of the banner and copyright notice when the Open Watcom Library Manager is invoked.

Example:

     wlib -v -l mylib

Explode Library File - "x" Option


The "x" option tells the Open Watcom Library Manager to extract all modules from the library.  Note that the modules are not deleted from the library.  Object modules will be placed in the current directory unless the "d" option is used to specify an alternate directory.

In the following example all modules will be extracted from the library "mylib.lib" and placed in the current directory.

Example:

     wlib -x mylib

In the following example, all modules will be extracted from the library "mylib.lib".  If you are running a DOS, OS/2 or Windows-hosted version of the Open Watcom Library Manager, the module will be placed in the "\obj" directory.  If you are running a UNIX-hosted version of the Open Watcom Library Manager, the module will be placed in the file "/o" directory.

Example:

     wlib -x -d=\obj mylib    DOS, OS/2 or Windows-hosted
         or
     wlib -x -d=/o mylib      UNIX-hosted

Librarian Error Messages


The following messages may be issued by the Open Watcom Library Manager.
Error!  Could not open object file '%s'.
Object file '%s' could not be found.  This message is usually issued when an attempt is made to add a non-existent object file to the library.

Error!  Could not open library file '%s'.
The specified library file could not be found.  This is usually issued for input library files.  For example, if you are combining two library files, the library file you are adding is an input library file and the library file you are adding to or creating is an output library file.

Error!  Invalid object module in file '%s' not added.
The specified file contains an invalid object module.

Error!  Dictionary too large.  Recommend split library into two libraries.
The size of the dictionary in a library file cannot exceed 64K.  You must split the library file into two separate library files.

Error!  Redefinition of module '%s' in file '%s'.
This message is usually issued when an attempt is made to add a module to a library that already contains a module by that name.

Warning!  Redefinition of symbol '%s' in file '%s' ignored.
This message is issued if a symbol defined by a module already in the library is also defined by a module being added to the library.

Error!  Library too large.  Recommend split library into two libraries or try a larger page_bound than %xH.
The record size of the library file does not allow the library file to increase beyond its current size.  The record size of the library file must be increased using the "p" option.

Error!  Expected '%s' in '%s' but found '%s'.
An error occurred while scanning command input.

Warning!  Could not find module '%s' for deletion.
This message is issued if an attempt is made to delete a module that does not exist in the library.

Error!  Could not find module '%s' for extraction.
This message is issued if an attempt is made to extract a module that does not exist in the library.

Error!  Could not rename old library for backup.
The Open Watcom Library Manager creates a backup copy before making any changes (unless the "b" option is specified).   This message is issued if an error occurred while trying to rename the original library file to the backup file name.

Warning!  Could not open library '%s' :  will be created.
The specified library does not exist.  It is usually issued when you are adding to a non-existent library.  The Open Watcom Library Manager will create the library.

Warning!  Output library name specification ignored.
This message is issued if the library file specified by the "o" option could not be opened.

Warning!  Could not open library '%s' and no operations specified:  will not be created.
This message is issued if the library file specified on the command line does not exist and no operations were specified.   For example, asking for a listing file of a non-existent library will cause this message to be issued.

Warning!  Could not open listing file '%s'.
The listing file could not be opened.  For example, this message will be issued when a "disk full" condition is present.

Error!  Could not open output library.
The output library could not be opened.

Error!  Unable to write to output library.
An error occurred while writing to the output library.

Error!  Unable to write to extraction file '%s'.
This message is issued when extracting an object module from a library file and an error occurs while writing to the output file.

Error!  Out of Memory.
There was not enough memory to process the library file.

Error!  Could not open file '%s'.
This message is issued if the output file for a module that is being extracted from a library could not be opened.

Error!  Library '%s' is invalid.  Contents ignored.
The library file does not contain the correct header information.

Error!  Library '%s' has an invalid page size.  Contents ignored.
The library file has an invalid record size.  The record size is contained in the library header and must be a power of 2.

Error!  Invalid object record found in file '%s'.
The specified file contains an invalid object record.

Error!  No library specified on command line.
This message is issued if a library file name is not specified on the command line.

Error!  Expecting library name.
This message is issued if the location of the library file name on the command line is incorrect.

Warning!  Invalid file name '%s'.
This message is issued if an invalid file name is specified.  For example, a file name longer that 127 characters is not allowed.

Error!  Could not open command file '%s'.
The specified command file could not be opened.

Error!  Could not read from file '%s'.  Contents ignored as command input.
An error occurred while reading a command file.

The Object File Disassembler


This chapter describes the Open Watcom Disassembler.  It takes as input an object file (a file with extension ".obj") and produces, as output, the Intel assembly language equivalent.  The Open Watcom compilers do not produce an assembly language listing directly from a source program.  Instead, the Open Watcom Disassembler can be used to generate an assembly language listing from the object file generated by the compiler.

The Open Watcom Disassembler command line syntax is the following. 

     
     WDIS [options] [d:][path]filename[.ext] [options]

The square brackets [ ] denote items which are optional.
WDIS
is the name of the Open Watcom Disassembler.

d:
is an optional drive specification such as "A:", "B:", etc.  If not specified, the default drive is assumed.

path
is an optional path specification such as "\PROGRAMS\OBJ\".  If not specified, the current directory is assumed.

filename
is the file name of the object file to disassemble.

ext
is the file extension of the object file to disassemble.  If omitted, a file extension of ".obj" is assumed.   If the period "." is specified but not the extension, the file is assumed to have no file extension.

options
is a list of valid options, each preceded by a slash ("/") or a dash ("-").  Options may be specified in any order.

The options supported by the Open Watcom Disassembler are:
a
write assembly instructions only to the listing file

e
include list of external names

ff
print FPU emulator fixups as comment line

fi
use alternate indexing format [80(x)86 only]

fp
do not use instruction name pseudonyms

fr
do not use register name pseudonyms [Alpha only]

fu
instructions/registers in upper case

i=<char>
redefine the initial character of internal labels (default:  L)

l[=<list_file>]
create a listing file

m
leave C++ names mangled

p
include list of public names

s[=<source_file>]
using object file source line information, imbed original source lines into the output file

The following sections describe the list of options.

Changing the Internal Label Character - "i=<char>"


The "i" option permits you to specify the first character to be used for internal labels.  Internal labels take the form "Ln" where "n" is one or more digits.  The default character "L" can be changed using the "i" option.  The replacement character must be a letter (a-z, A-Z).  A lowercase letter is converted to uppercase.

Example:

     C>wdis calendar -i=x

The Assembly Format Option - "a"


The "a" option controls the format of the output produced to the listing file.  When specified, the Open Watcom Disassembler will produce a listing file that can be used as input to an assembler.

Example:

     C>wdis calendar -a -l=calendar.asm

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file calendar.obj and produce the output to the file calendar.asm so that it can be assembled by an assembler.

The External Symbols Option - "e"


The "e" option controls the amount of information produced in the listing file.  When specified, a list of all externally defined symbols is produced in the listing file.

Example:

     C>wdis calendar -e

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file calendar.obj and produce the output, with a list of all external symbols, on the screen.  A sample list of external symbols is shown below.

     
     List of external symbols

     Symbol
     ----------------
     ___iob           0000032f 00000210 000001f4 00000158 00000139
     __CHK            00000381 00000343 000002eb 00000237 000000cb 00000006
     Box_             000000f2
     Calendar_        000000a7 00000079 00000049
     ClearScreen_     00000016
     fflush_          00000334 00000215 000001f9 0000015d 0000013e
     int386_          000003af 00000372
     Line_            000002db 000002b5 00000293 00000274 0000025a
     localtime_       00000028
     memset_          00000308
     PosCursor_       0000031e 000001e1 00000148 00000123 000000b6
     printf_          00000327 00000208 000001ec 00000150 00000131
     strlen_          00000108
     time_            0000001d
     ------------------------------------------------------------

Each externally defined symbol is followed by a list of location counter values indicating where the symbol is referenced.

The "e" option is ignored when the "a" option is specified.

The FPU emulator fixups Option - "ff"


The "ff" option causes the FPU emulator fixups will be printed as comment line before Intel FPU instruction.

     
         ; FPU fixup FIDRQQ
         fld         tbyte ptr [bx]

The Alternate Addressing Form Option - "fi"


The "fi" option causes an alternate syntactical form of the based or indexed addressing mode of the 80x86 to be used in an instruction.  For example, the following form is used by default for Intel instructions.

     
     mov ax,-2[bp]

If the "fi" option is specified, the following form is used.

     
     mov ax,[bp-2]

The No Instruction Name Pseudonyms Option - "fp"


By default, AXP instruction name pseudonyms are emitted in place of actual instruction names.  The Open Watcom AXP Assembler accepts instruction name pseudonyms.  The "fp" option instructs the Open Watcom Disassembler to emit the actual instruction names instead.

The No Register Name Pseudonyms Option - "fr"


By default, AXP register names are emitted in pseudonym form.  The Open Watcom AXP Assembler accepts register pseudonyms.   The "fr" option instructs the Open Watcom Disassembler to display register names in their non-pseudonym form.

The Uppercase Instructions/Registers Option - "fu"


The "fu" option instructs the Open Watcom Disassembler to display instruction and register names in uppercase characters.  The default is to display them in lowercase characters.

The Listing Option - "l[=<list_file>]"


By default, the Open Watcom Disassembler produces its output to the terminal.  The "l" (lowercase L) option instructs the Open Watcom Disassembler to produce the output to a listing file.  The default file name of the listing file is the same as the file name of the object file.  The default file extension of the listing file is .lst.

Example:

     C>wdis calendar -l

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file calendar.obj and produce the output to a listing file called calendar.lst.

An alternate form of this option is "l=<list_file>".  With this form, you can specify the name of the listing file.  When specifying a listing file, a file extension of .lst is assumed if none is specified.

Example:

     C>wdis calendar -l=calendar.lis

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file calendar.obj and produce the output to a listing file called calendar.lis.

The Public Symbols Option - "p"


The "p" option controls the amount of information produced in the listing file.  When specified, a list of all public symbols is produced in the listing file.

Example:

     C>wdis calendar -p

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file calendar.obj and produce the output, with a list of all exported symbols, to the screen.  A sample list of public symbols is shown below.

The following is a list of public symbols in 80x86 code.

     
     List of public symbols

     SYMBOL                   SECTION                  OFFSET
     --------------------------------------------------------
     main_                    _TEXT                    000002C0
     void near Box( int, int, int, int )
                              _TEXT                    00000093
     void near Calendar( int, int, int, int, int, char near * )
                              _TEXT                    0000014A
     void near ClearScreen() _TEXT                    00000000
     void near Line( int, int, int, char, char, char )
                              _TEXT                    00000036
     void near PosCursor( int, int )
                              _TEXT                    0000001A

The following is a list of public symbols in Alpha AXP code.

     
     List of public symbols

     SYMBOL                   SECTION                  OFFSET
     --------------------------------------------------------
     main                     .text                    000004F0
     void near Box( int, int, int, int )
                              .text                    00000148
     void near Calendar( int, int, int, int, int, char near * )
                              .text                    00000260
     void near ClearScreen() .text                    00000000
     void near Line( int, int, int, char, char, char )
                              .text                    00000060
     void near PosCursor( int, int )
                              .text                    00000028

The "p" option is ignored when the "a" option is specified.

Retain C++ Mangled Names - "m"


The "m" option instructs the Open Watcom Disassembler to retain C++ mangled names rather than displaying their demangled form.  The default is to interpret mangled C++ names and display them in a somewhat more intelligible form.

The Source Option - "s[=<source_file>]"


The "s" option causes the source lines corresponding to the assembly language instructions to be produced in the listing file.  The object file must contain line numbering information.  That is, the "d1" or "d2" option must have been specified when the source file was compiled.  If no line numbering information is present in the object file, the "s" option is ignored.

The following defines the order in which the source file name is determined when the "s" option is specified.
  1. If present, the source file name specified on the command line.
  2. The name from the module header record.
  3. The object file name.

In the following example, we have compiled the source file mysrc.c with "d1" debugging information.   We then disassemble it as follows:

Example:

     C>wdis mysrc -s -l

In the above example, the Open Watcom Disassembler is instructed to disassemble the contents of the file mysrc.obj and produce the output to the listing file mysrc.lst.  The source lines are extracted from the file mysrc.c.

An alternate form of this option is "s=<source_file>".  With this form, you can specify the name of the source file.

Example:

     C>wdis mysrc -s=myprog.c -l

The above example produces the same result as in the previous example except the source lines are extracted from the file myprog.c.

An Example


Consider the following program contained in the file hello.c.

     #include <stdio.h>

     void main()
     {
         printf( "Hello world\n" );
     }

Compile it with the "d1" option.  An object file called hello.obj will be produced.  The "d1" option causes line numbering information to be generated in the object file.  We can use the Open Watcom Disassembler to disassemble the contents of the object file by issuing the following command.

     
     C>wdis hello -l -e -p -s -fu

The output will be written to a listing file called hello.lst (the "l" option was specified").   It will contain a list of external symbols (the "e" option was specified), a list of public symbols (the "p" option was specified) and the source lines corresponding to the assembly language instructions (the "s" option was specified).  The source input file is called hello.c.  The register names will be displayed in upper case (the "fu" option was specified).  The output, shown below, is the result of using the Open Watcom C++ compiler.

The following is a disassembly of 80x86 code.

     
     Module: HELLO.C
     GROUP: 'DGROUP' CONST,CONST2,_DATA,_BSS

     Segment: _TEXT DWORD USE32 0000001A bytes

     #include <stdio.h>

     void main()
     0000                     main_:
     0000    68 08 00 00 00      PUSH       0x00000008
     0005    E8 00 00 00 00      CALL       __CHK

     {
         printf( "Hello world\n" );
     000A    68 00 00 00 00      PUSH       offset L$1
     000F    E8 00 00 00 00      CALL       printf_
     0014    83 C4 04             ADD       ESP,0x00000004

     }
     0017    31 C0                XOR       EAX,EAX
     0019    C3                   RET

     Routine Size: 26 bytes,    Routine Base: _TEXT + 0000

     No disassembly errors

     List of external references

     SYMBOL
     -------
     __CHK                    0006
     printf_                  0010

     Segment: CONST DWORD USE32 0000000D bytes
     0000                     L$1:
     0000    48 65 6C 6C 6F 20 77 6F 72 6C 64 0A 00           Hello world..

     BSS Size: 0 bytes

     List of public symbols

     SYMBOL                   SECTION                  OFFSET
     --------------------------------------------------------
     main_                    _TEXT                    00000000

The following is a disassembly of Alpha AXP code.

     
                                      .new_section .text, "crx4"

     #include <stdio.h>

     void main()
     0000                     main:
     0000    23DEFFF0             LDA           SP,-0x10(SP)
     0004    B75E0000             STQ           RA,(SP)

     {
         printf( "Hello world\n" );
     0008    261F0000             LDAH          A0,h^L$0(R31)
     000C    22100000             LDA           A0,l^L$0(A0)
     0010    43F00010             SEXTL         A0,A0
     0014    D3400000             BSR           RA,j^printf

     }
     0018    201F0000             MOV           0x00000000,V0
     001C    A75E0000             LDQ           RA,(SP)
     0020    23DE0010             LDA           SP,0x10(SP)
     0024    6BFA8001             RET           (RA)

     Routine Size: 40 bytes,    Routine Base: .text + 0000

     No disassembly errors

     List of external references

     SYMBOL
     -------
     printf                   0014

                                      .new_section .const, "drw4"
     0000                     L$0:
     0000    48 65 6C 6C 6F 20 77 6F 72 6C 64 0A 00 00 00 00 Hello world.....

                                      .new_section .const2, "drw4"

                                      .new_section .data, "drw4"

                                      .new_section .bss, "urw4"
     0000                     .bss:

     BSS Size: 0 bytes

                                      .new_section .pdata, "dr2"

     0000                     //  Procedure descriptor for main
             main                                      //  BeginAddress      : 0
             main+0x28                                 //  EndAddress        : 40
             00000000                                  //  ExceptionHandler  : 0
             00000000                                  //  HandlerData       : 0
             main+0x8                                  //  PrologEnd         : 8

                                      .new_section .drectve, "iRr0"
     0000    2D 64 65 66 61 75 6C 74 6C 69 62 3A 63 6C 69 62 -defaultlib:clib
     0010    20 2D 64 65 66 61 75 6C 74 6C 69 62 3A 70 6C 69  -defaultlib:pli
     0020    62 20 2D 64 65 66 61 75 6C 74 6C 69 62 3A 6D 61 b -defaultlib:ma
     0030    74 68 20 00                                       th .

     List of public symbols

     SYMBOL                   SECTION                  OFFSET
     --------------------------------------------------------
     main                     .text                    00000000

Let us create a form of the listing file that can be used as input to an assembler.

     
     C>wdis hello -l=hello.asm -r -a

The output will be produced in the file hello.asm.  The output, shown below, is the result of using the Open Watcom C++ compiler.

The following is a disassembly of 80x86 code.

     
     .387
     .386p
                      PUBLIC  main_
                      EXTRN   __CHK:BYTE
                      EXTRN   printf_:BYTE
                      EXTRN   ___wcpp_3_data_init_fs_root_:BYTE
                      EXTRN   _cstart_:BYTE
     DGROUP          GROUP   CONST,CONST2,_DATA,_BSS
     _TEXT           SEGMENT DWORD PUBLIC USE32 'CODE'
                      ASSUME CS:_TEXT, DS:DGROUP, SS:DGROUP
     main_:
         PUSH      0x00000008
         CALL      near ptr __CHK
         PUSH      offset L$1
         CALL      near ptr printf_
         ADD       ESP,0x00000004
         XOR       EAX,EAX
         RET
     _TEXT           ENDS

     CONST           SEGMENT DWORD PUBLIC USE32 'DATA'
     L$1:
                      DB      0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x77, 0x6f
                      DB      0x72, 0x6c, 0x64, 0x0a, 0x00

     CONST           ENDS
     CONST2          SEGMENT DWORD PUBLIC USE32 'DATA'
     CONST2          ENDS
     _DATA           SEGMENT DWORD PUBLIC USE32 'DATA'
     _DATA           ENDS
     _BSS            SEGMENT DWORD PUBLIC USE32 'BSS'
     _BSS            ENDS

                      END

The following is a disassembly of Alpha AXP code.
     
     .globl          main
     .extrn          printf
     .extrn          _cstart_
     .new_section .text, "crx4"
     main:
         LDA           $SP,-0x10($SP)
         STQ           $RA,($SP)
         LDAH          $A0,h^`L$0`($ZERO)
         LDA           $A0,l^`L$0`($A0)
         SEXTL         $A0,$A0
         BSR           $RA,j^printf
         MOV           0x00000000,$V0
         LDQ           $RA,($SP)
         LDA           $SP,0x10($SP)
         RET           $ZERO,($RA),0x00000001

     .new_section .const, "drw4"
     `L$0`:
                      .asciiz "Hello world\n"
                      .byte   0x00, 0x00, 0x00

     .new_section .pdata, "dr2"

                      //  0000                Procedure descriptor for main
                      .long   main                     //  BeginAddress      : 0
                      .long   main+0x28               //   EndAddress        : 40
                      .long   00000000                //  ExceptionHandler  : 0
                      .long   00000000                //  HandlerData       : 0
                      .long   main+0x8                //  PrologEnd         : 8

     .new_section .drectve, "iRr0"
                      .asciiz "-defaultlib:clib -defaultlib:plib -defaultlib:math "

Optimization of Far Calls


Optimization of far calls can result in smaller executable files and improved performance.  It is most useful when the automatic grouping of logical segments into physical segments takes place.  Note that, by default, automatic grouping is performed by the Open Watcom Linker.

The Open Watcom C, C++ and FORTRAN 77 compilers automatically enable the far call optimization.  The Open Watcom Linker will optimize far calls to procedures that reside in the same physical segment as the caller.  For example, a large code model program will probably contain many far calls to procedures in the same physical segment.  Since the segment address of the caller is the same as the segment address of the called procedure, only a near call is necessary.   A near call does not require a relocation entry in the relocation table of the executable file whereas a far call does.   Thus, the far call optimization will result in smaller executable files that will load faster.  Furthermore, a near call will generally execute faster than a far call, particularly on 286 and 386-based machines where, for applications running in protected mode, segment switching is fairly expensive.

The following describes the far call optimization.  The call far label instruction is converted to one of the following sequences of code.

     
     push   cs                 seg    ss
     call   near label        push   cs
     nop                       call   near label

Notes:
  1. The nop or seg ss instruction is present since a call far label instruction is five bytes.  The push cs instruction is one byte and the call near label instruction is three bytes.  The seg ss instruction is used because it is faster than the nop instruction.
  2. The called procedure will still use a retf instruction but since the code segment and the near address are pushed on the stack, the far return will execute correctly.
  3. The position of the padding instruction is chosen so that the return address is word aligned.  A word aligned return address improves performance.
  4. When two consecutive call far label instructions are optimized and the first call far label instruction is word aligned, the following sequence replaces both call far label instructions.

         
         push    cs
         call    near label1
         seg     ss
         push    cs
         seg     cs
         call    near label2
  5. If your program contains only near calls, this optimization will have no effect.

A far jump optimization is also performed by the Open Watcom Linker.  This has the same benefits as the far call optimization.  A jmp far label instruction to a location in the same segment will be replaced by the following sequence of code.

     
     jmp    near label
     mov    ax,ax

Note that for 32-bit segments, this instruction becomes mov eax,eax.

Far Call Optimizations for Non-Open Watcom Object Modules


The far call optimization is automatically enabled when object modules created by the Open Watcom C, C++, or FORTRAN 77 compilers are linked.  These compilers mark those segments in which this optimization can be performed.  The following utility can be used to enable this optimization for object modules that have been created by other compilers or assemblers.

The Open Watcom Far Call Optimization Enabling Utility


Only DOS, OS/2 and Windows-hosted versions of the Open Watcom Far Call Optimization Enabling Utility are available.  A QNX-hosted version is not necessary since QNX-hosted development tools that generate object files, generate the necessary information that enables the far call optimization.

The format of the Open Watcom Far Call Optimization Enabling Utility is as follows.  Items enclosed in square brackets are optional; items enclosed in braces may be repeated zero or more times.

     
     FCENABLE { [option] [file] }
where
description

option
is an option and must be preceded by a dash ('-') or slash ('/').

file
is a file specification for an object file or library file.  If no file extension is specified, a file extension of "obj" is assumed.  Wild card specifiers may be used.

The following describes the command line options. 
b
Do not create a backup file.  By default, a backup file will be created.  The backup file name will have the same file name as the input file and a file extension of "bob" for object files and "bak" for library files.  

c
Specify a list of class names, each separated by a comma.  This enables the far call optimization for all segments belonging to the specified classes. 

s
Specify a list of segment names, each separated by a comma.  This enables the far call optimization for all specified segments. 

x
Specify a list of ranges, each separated by a comma, for which no far call optimizations are to be made.  A range has the following format.
     
     seg_name start-end
             or
     seg_name start:length

seg_name is the name of a segment.  start is an offset into the specified segment defining the start of the range.  end is an offset into the specified segment defining the end of the range.  length is the number of bytes from start to be included in the range.  All values are assumed to be hexadecimal.

Notes:
  1. If more than one class list or segment list is specified, only the last one is used.  A class or segment list applies to all object and library files regardless of their position relative to the class or segment list.
  2. A range list applies only to the first object file following the range specification.  If the object file contains more than one module, the range list will only apply to the first module in the object file.

The following examples illustrate the use of the Open Watcom Far Call Optimization Enabling Utility.

Example:

     fcenable -c code *.obj

In the above example, the far call optimization will be enabled for all segments belonging to the "code" class.

Example:

     fcenable -s _text *.obj

In the above example, the far call optimization will be enabled for all segments with name "_text".

Example:

     fcenable -x special 0:400 asmfile.obj

In the above example, the far call optimization will be disabled for the first 1k bytes of the segment named "special" in the object file "asmfile".

Example:

     fcenable -x special 0-ffffffff asmfile.obj

In the above example, the far call optimization will be disabled for the entire segment named "special" in the object file "asmfile".

The Open Watcom Exe2bin Utility


The exe2bin utility strips off the header of a DOS executable file and applies any necessary fixups.  In addition, it is able to display the header and relocations of an executable file in human readable format.

When DOS executes a program (supplied as an ".exe" file) it first reads the header of the executable file and ensures there is enough memory to load the program.  If there is, DOS loads the file - excluding the header - to memory.  Before jumping to the entry point, DOS has to adjust a number of certain locations that depend on the load address of the program.  These adjustments consist of the addition of the load address to each entry in the above mentioned list of relocations.  These relocations are part of the header of an executable file.  The load address may vary from invocation to invocation, this creates the need for the existence of relocations.

As exe2bin strips the executable header, the relocations are lost (among other things).  This would render the resulting output useless, if exe2bin were not to apply the relocations as part of the conversion process.  Just like DOS, exe2bin therefore needs to know the load address.  This is supplied via an argument to exe2bin.

Some programs do not rely on the address they are being loaded at, and consequently do not contain any relocations.   In this case exe2bin merely copies the contents of the input file (apart from the header) to the output file.

The phrase "binary part" (also "binary data") is used as a technical term in the documentation of exe2bin.  It denotes the data following the header.  The length of the binary data is determined by the header entries "Size mod 512", "Number of pages" and "Size of header".  It is not directly related to the actual size of the input file.

  Note:  Although Open Watcom Exe2bin is capable of producing DOS ".COM" executables, this functionality is only provided for compatibility with other tools.  The preferred way of generating ".COM" executables is to use the Open Watcom Linker with directive "format dos com".  Refer to the Open Watcom Linker Guide for details.

The Open Watcom Exe2bin Utility Command Line


The format of the Open Watcom Exe2bin command line is as follows.  Items enclosed in square brackets ("[ ]") are optional.

     
     EXE2BIN [options] exe_file [bin_file]
where
description

options
is a list of options, each preceded by a dash ("-").  On non-UNIX platforms, a slash ("/") may be also used instead of a dash.  Options may be specified in any order.  Supported options are:
h
display the executable file header

r
display the relocations of the executable file

l=<seg>
specify the load address of the binary file

x
enable extended capabilities of Open Watcom Exe2bin

exe_file
is a file specification for a 16-bit DOS executable file used as input.  If no file extension is specified, a file extension of ".exe" is assumed.  Wild card specifiers may not be used.

bin_file
is an optional file specification for a binary output file.  If no file name is given, the extension of the input file is replaced by "bin" and taken as the name for the binary output file.

Description:
  1. If are any relocations in the input file, the -l option becomes mandatory (and is useless otherwise).
  2. If exe2bin is called without the -x option, certain restrictions to the input file apply (apart from being a valid DOS executable file):
    None of the above restrictions apply if the -x option is supplied.
  3. If cs:ip = 0x0000:0x0100 and the -x option is not specified, no relocations are allowed in the input file.  Furthermore, exe2bin skips another 0x100 bytes following the header (in addition to the latter).

    This behaviour allows the creation of DOS ".COM" executables and is implemented for backward compatibility.   It is however strongly suggested to use the Open Watcom Linker instead (together with directive "format dos com" ).

The examples below illustrate the use of Open Watcom Exe2bin.

Example:

     exe2bin prog.exe

Strips off the executable header from prog.exe and writes the binary part to prog.bin.  If there are any relocations in prog.exe or if the input file violates any of the restrictions listed above, the execution of exe2bin fails.

Example:

     exe2bin -x prog.exe

Same as above but the "-x" option relaxes certain restrictions.

  Note:  Even if exe2bin is sucessfully invoked with identical input files as in the preceding examples (i.e.  with vs.  without -x) the output files may differ.  This happens when cs:ip = 0x0000:0x0100 causes exe2bin to skip additional 0x100 bytes from the input file, if the user did not specify -x.

Example:

     exe2bin -h prog.exe test.bin

Displays the header of prog.exe, strips it off and copies the binary part to test.bin.

Example:

     exe2bin -h -r -x -l=0xE000 bios.exe bios.rom

Displays the header and the relocations (if any) of bios.exe strips the header and applies any fixups to (i.e.  relocates) bios.exe as if it were to be loaded at 0xE000:0x0000.  The result will be written to bios.rom

The above command line may serve as an example of creating a 128 KByte BIOS image for the PC-AT architecture.

Exe2bin Messages


This is a list of the diagnostic messages exe2bin may display, accompanied by more verbose descriptions and some possible causes.
Error opening %s for reading.
The input executable file could not be opened for reading.
Check that the input file exists and exe2bin has read permissions.

Error opening %s for writing.
The output binary file could not be opened for writing.
Make sure the media is not write protected, has enough free space to hold the output file, and exe2bin has write permissions.

Error allocating file I/O buffer.
There is not enough free memory to allocate a file buffer.

Error reading while copying data.
An error occured while reading the binary part of the input file.
This is most likely due to a corrupted executable header.  Run exe2bin with the -h option and check the size reported.   The size of the input file must be at least ("Number of pages" - 1) * 512 + "Size mod 512".  Omit decrementing the number of pages if "Size mod 512" happens to equal zero.

Error writing while copying data.
The output binary file can not be written to.
Make sure the media has enough free space to hold the output file and is not removed while writing to it.

Error.  %s has no valid executable header.
The signature (the first two bytes of the input file) does not match "MZ".
exe2bin can only use valid DOS executable files as input.

Error allocating/reading reloc-table.
There is either not enough free memory to allocate a buffer for the relocations (each relocation takes about 4 bytes) or there was an error while reading from the input file.

Error.  Option "-l=<seg>" mandatory (there are relocations).
The executable file contains relocations.  Therefore, exe2bin needs to know the segment the binary output file is supposed to reside at.
Either provide a segment as an argument to the -l option or rewrite your executable file to not contain any relocations.

Error:  Binary part exceeds 64 KBytes.
The binary part of the input file is larger than 64 KBytes.
The restriction applies because the -x option was not specified.  Check if the extended behaviour is suitable or rewrite the program to shorten the binary part.

Error:  Stack segment defined.
The header defines an initial stack, i.e.  ss:sp != 0x0000:0x0000.
The restriction applies because the -x option was not specified.  Check if the extended behaviour is suitable or rewrite the program to not have a segment of class "stack".

Error:  CS:IP neither 0x0000:0x0000 nor 0x0000:0x0100.
The header defines an initial cs:ip not matching any of the two values.
The restriction applies because the -x option was not specified.  Check if the extended behaviour is suitable or rewrite the program to have a different entry point (cf.  Open Watcom Linker "option start" ).

Error:  com-file must not have relocations.
Although the binary part is <= 64 KByte in length, there is no stack defined and the cs:ip is 0x0000:0x0100, i.e.  exe2bin assumes you try to generate a ".COM" executable, there are relocations in the input file.
".COM" files are not allowed to contain relocations.  Either produce an ".EXE" file instead or rewrite the program to avoid the need for relocations.  In order to do the latter, look for statements that refer to segments or groups such as mov ax, _TEXT or mov ax, DGROUP.

The Open Watcom Patch Utility


The Open Watcom Patch Utility is a utility program which may be used to apply patches or bug fixes to Open Watcom's compilers and its associated tools.  As problems are reported and fixed, patches are created and made available on Open Watcom's BBS, Open Watcom's FTP site, or CompuServe for users to download and apply to their copy of the tools.

Applying a Patch


The format of the BPATCH command line is: 

     
     BPATCH [options] patch_file

The square brackets [ ] denote items which are optional.
where
description

options
is a list of valid Open Watcom Patch Utility options, each preceded by a dash ("-").  Options may be specified in any order.  The possible options are:
-p
Do not prompt for confirmation

-b
Do not create a .BAK file

-q
Print current patch level of file

patch_file
is the file specification for a patch file provided by Open Watcom.

Suppose a patch file called "wlink.a" is supplied by Open Watcom to fix a bug in the file "WLINK.EXE".   The patch may be applied by typing the command:

     
     bpatch wlink.a

The Open Watcom Patch Utility locates the file C:\WATCOM\BINW\WLINK.EXE using the PATH environment variable.  The actual name of the executable file is extracted from the file wlink.a.  It then verifies that the file to be patched is the correct one by comparing the size of the file to be patched to the expected size.  If the file sizes match, the program responds with:

     
     Ok to modify 'C:\WATCOM\BINW\WLINK.EXE'? [y|n]

If you respond with "yes", BPATCH will modify the indicated file.  If you respond with "no", BPATCH aborts.  Once the patch has been applied the resulting file is verified.  First the file size is checked to make sure it matches the expected file size.  If the file size matches, a check-sum is computed and compared to the expected check-sum.

Notes:
  1. If an error message is issued during the patch process, the file that you specified to be patched will remain unchanged.
  2. If a sequence of patch files exist, such as "wlink.a", "wlink.b" and "wlink.c", the patches must be applied in order.  That is, "wlink.a" must be applied first followed by "wlink.b" and finally "wlink.c".

Diagnostic Messages


If the patch cannot be successfully applied, one of the following error messages will be displayed.
Usage:  BPATCH {-p} {-q} {-b} <file>
-p = Do not prompt for confirmation
-b = Do not create a .BAK file
-q = Print current patch level of file
The command line was entered with no arguments.

File '%s' has not been patched
This message is issued when the "-q" option is used and the file has not been patched.

File '%s' has been patched to level '%s'
This message is issued when the "-q" option is used and the file has been patched to the indicated level.

File '%s' has already been patched to level '%s' - skipping
This message is issued when the file has already been patched to the same level or higher.

Command line may only contain one file name
More than one file name is specified on the command line.  Make sure that "/" is not used as an option delimiter.

Command line must specify a file name
No file name has been specified on the command line.

'%s' is not a Open Watcom patch file
The patch file is not of the required format.  The required header information is not present.

'%s' is not a valid Open Watcom patch file
The patch file is not of the required format.  The required header information is present but the remaining contents of the file have been corrupted.

'%s' is the wrong size (%lu1).  Should be (%lu2)
The size of the file to be patched (%lu1) is not the same as the expected size (%lu2).

Cannot find '%s'
Cannot find the executable to be patched.

Cannot open '%s'
An error occurred while trying to open the patch file, the file to be patched or the resulting file.

Cannot read '%s'
An input error occurred while reading the old version of the file being patched.

Cannot rename '%s' to '%s'
The file to be patched could not be renamed to the backup file name or the resulting file could not be renamed to the name of the file that was patched.

Cannot write to '%s'
An output error occurred while writing to the new version of the file to be patched.

I/O error processing file '%s'
An error occurred while seeking in the specified file.

No memory for %s
An attempt to allocate memory dynamically failed.

Patch program aborted!
This message is issued if you answered no to the "OK to modify" prompt.

Resulting file has wrong checksum (%lu) - Should be (%lu2)
The check-sum of the resulting file (%lu) does not match the expected check-sum (%lu2).  This message is issued if you have patched the wrong version.

Resulting file has wrong size (%lu1) - Should be (%lu2)
The size of the resulting file (%lu1) does not match the expected size (%lu2).  This message is issued if you have patched the wrong version.

The Open Watcom Strip Utility


The Open Watcom Strip Utility may be used to manipulate information that is appended to the end of an executable file.   The information can be either one of two things:
  1. Symbolic debugging information
  2. Resource information

This information can be added or removed from the executable file.  Symbolic debugging information is placed at the end of an executable file by the Open Watcom Linker or the Open Watcom Strip Utility.  Resource information is placed at the end of an executable by a resource compiler or the Open Watcom Strip Utility.

Once a program has been debugged, the Open Watcom Strip Utility allows you to remove the debugging information from the executable file so that you do not have to remove the debugging directives from the linker directive file and link your program again.  Removal of the debugging information reduces the size of the executable image.

All executable files generated by the Open Watcom Linker can be specified as input to the Open Watcom Strip Utility.   Note that for executable files created for Novell's NetWare operating system, debugging information created using the "NOVELL" option in the "DEBUG" directive cannot be removed from the executable file.  You must remove the "DEBUG" directive from the directive file and re-link your application.

The Open Watcom Strip Utility currently runs under the following operating systems.

The Open Watcom Strip Utility Command Line


The Open Watcom Strip Utility command line syntax is: 

     
     WSTRIP [options] input_file [output_file] [info_file]
where:

[]
The square brackets denote items which are optional.

options
-b
(backup) Create backup (.bak) file for input executable.

-n
(noerrors) Do not issue any diagnostic message.

-q
(quiet) Do not print any informational messages.

-r
(resources) Process resource information rather than debugging information.

-a
(add) Add information rather than remove information.

input_file
is a file specification for the name of an executable file.  If no file extension is specified, the Open Watcom Strip Utility will assume one of the following extensions:  "exe", "dll", "exp", "rex", "nlm", "dsk", "lan", "nam", "msl", "cdm", "ham", "qnx" or no file extension.  Note that the order specified in the list of file extensions is the order in which the Open Watcom Strip Utility will select file extensions.

output_file
is an optional file specification for the output file.  If no file extension is specified, the file extension specified in the input file name will be used for the output file name.  If "." is specified, the input file name will be used.

info_file
is an optional file specification for the file in which the debugging or resource information is to be stored (when removing information) or read (when adding information).  If no file extension is specified, a file extension of "sym" is assumed for debugging information and "res" for resource information.  To specify the name of the information file but not the name of an output file, a "." may be specified in place of output_file.

Description:
  1. If the "r" (resource) option is not specified then the default action is to add/remove symbolic debugging information.
  2. If the "a" (add) option is not specified then the default action is to remove information.
  3. If output_file is not specified, the debugging or resource information is added to or removed from input_file.
  4. If output_file is specified, input_file is copied to output_file and the debugging or resource information is added to or removed from output_file.  input_file remains unchanged.
  5. If info_file is specified then the debugging or resource information that is added to or removed from the executable file is read from or written to this file.  The debugging or resource information may be appended to the executable by specifying the "a" (add) option.  Also, the debugging information may be appended to the executable by concatenating the debugging information file to the end of the executable file (the files must be treated as binary files).
  6. During processing, the Open Watcom Strip Utility will create a temporary file, ensuring that a file by the chosen name does not already exist.

Strip Utility Messages


The following messages may be issued by the Open Watcom Strip Utility.
Usage:  WSTRIP [options] input_file [output_file] [info_file]
options:  (-option is also accepted)
      /n     don't print warning messages
      /q     don't print informational messages
      /r     process resource information rather than debugging information
      /a     add information rather than delete information
input_file:  executable file
output_file:  optional output executable or '.'
info_file:  optional output debugging or resource information file
             or input debugging or resource informational file
The command line was entered with no arguments.

Too low on memory
There is not enough free memory to allocate file buffers.

Unable to find '%s'
The specified file could not be located.

Cannot create temporary file
All the temporary file names are in use.

Unable to open '%s' to read
The input executable file cannot be opened for reading.

'%s' is not a valid executable file
The input file has invalid executable file header information.

'%s' does not contain debugging information
There is nothing to strip from the specified executable file.

Seek error on '%s'
An error occurred during a seek operation on the specified file.

Unable to create output file '%s'
The output file could not be created.  Check that the output disk is not write-protected or that the specified output file is not marked "read-only".

Unable to create symbol file '%s'
The symbol file could not be created.

Error reading '%s'
An error occurred while reading the input executable file.

Error writing to '%s'
An error occurred while writing the output executable file or the symbol file.  Check the amount of free space on the output disk.  If the input and output files reside on the same disk, there might not be enough room for a second copy of the executable file during processing.

Cannot erase file '%s'
The input executable file is probably marked "read-only" and therefore could not be erased (the input file is erased whenever the output file has the same name).

Cannot rename file '%s'
The output executable file could not be renamed.  Ordinarily, this should never occur.

The Open Watcom Make Utility


The Open Watcom Make utility is useful in the development of programs and text processing but is general enough to be used in many different applications.  Make uses the fact that each file has a time-stamp associated with it that indicates the last time the file was updated.  Make uses this time-stamp to decide which files are out of date with respect to each other.  For instance, if we have an input data file and an output report file we would like the output report file to accurately reflect the contents of the input data file.  In terms of time-stamps, we would like the output report to have a more recent time-stamp than the input data file (we will say that the output report file should be "younger" than the input data file).  If the input file had been modified then we would know from the younger time-stamp (in comparison to the report file) that the report file was out of date and should be updated.  Make may be used in this and many other situations to ensure that files are kept up to date.

Some readers will be quite familiar with the concepts of the Make file maintenance tool.  Open Watcom Make is patterned after the Make utility found on UNIX systems.  The next major section is simply intended to summarize, for reference purposes only, the syntax and options of Make's command line and special macros.  Subsequent sections go into the philosophy and capabilities of Open Watcom Make.  If you are not familiar with the capabilities of the Make utility, we recommend that you skip to the next major section entitled "Dependency Declarations" and read on.

Open Watcom Make Reference


The following sub-sections serve as a reference guide to the Open Watcom Make utility.

Open Watcom Make Command Line Format


The formal Open Watcom Make command line syntax is shown below. 

     
     WMAKE [options] [macro_defs] [targets]

As indicated by the square brackets [ ], all items are optional.
options
is a list of valid Open Watcom Make options, each preceded by a dash ("-").  Alternatively, a slash ("/") can be used on non-UNIX systems.  Options may be specified in any order.

macro_defs
is a list of valid Open Watcom Make macro definitions.  Macro definitions are of the form:
     
     A=B

and are readily identified by the presence of the "=".  Surround the definition with quotes (") if it contains blanks (e.g., "debug_opt=debug all").  The macro definitions specified on the command line supersede any macro definitions defined in makefiles.  Macro names are case-insensitive unless the "ms" option is used to select Microsoft NMAKE mode. 

targets
is one or more targets described in the makefile.

Open Watcom Make Options Summary


In this section, we present a terse summary of the Open Watcom Make options.  This summary is displayed on the screen by simply entering "WMAKE ?" on the command line.

Example:

     C>wmake ?
-a
make all targets by ignoring time-stamps

-b
block/ignore all implicit rules

-c
do not verify the existence of files made

-d
debug mode - echo all work as it progresses

-e
always erase target after error/interrupt (disables prompting)

-f
the next parameter is a name of dependency description file

-h
do not print out Make identification lines (no header)

-i
ignore return status of all commands executed

-k
on error/interrupt:  continue on next target

-l
the next parameter is the name of a output log file

-m
do not search for MAKEINIT file

-ms
Microsoft NMAKE mode

-n
no execute mode - print commands without executing

-o
use circular implicit rule path

-p
print the dependency tree as understood from the file

-q
query mode - check targets without updating them

-r
do not use default definitions

-s
silent mode - do not print commands before execution

-sn
noisy mode - always print commands before execution

-t
touch files instead of executing commands

-u
UNIX compatibility mode

-v
verbose listing of inline files

-y
show why a target will be updated

-z
do not erase target after error/interrupt (disables prompting)

Command Line Options


Command line options, available with Open Watcom Make, allow you to control the processing of the makefile.

a


make all targets by ignoring time-stamps
The "a" option is a safe way to update every target.  For program maintenance, it is the preferred method over deleting object files or touching source files.

b


block/ignore all implicit rules
The "b" option will indicate to Make that you do not want any implicit rule checking done.  The "b" option is useful in makefiles containing double colon "::" explicit rules because an implicit rule search is conducted after a double colon "::" target is updated.  Including the directive .BLOCK in a makefile also will disable implicit rule checking.

c


do not verify the existence of files made
Make will check to ensure that a target exists after the associated command list is executed.  The target existence checking may be disabled with the "c" option.  The "c" option is useful in processing makefiles that were developed with other Make utilities.  The .NOCHECK directive is used to disable target existence checks in a makefile.

d


debug mode - echo all work as it progresses
The "d" option will print out information about the time-stamp of files and indicate how the makefile processing is proceeding.

e


always erase target after error/interrupt (disables prompting)
The "e" option will indicate to Make that, if an error or interrupt occurs during makefile processing, the current target being made may be deleted without prompting.  The .ERASE directive may be used as an equivalent option in a makefile.

f


the next parameter is a name of dependency description file
The "f" option specifies that the next parameter on the command line is the name of a makefile which must be processed.  If the "f" option is specified then the search for the default makefile named "MAKEFILE" is not done.  Any number of makefiles may be processed with the "f" option.

Example:

     wmake /f myfile
     wmake /f myfile1 /f myfile2

h


do not print out Make identification lines (no header)
The "h" option is useful for less verbose output.  Combined with the "q" option, this allows a batch file to silently query if an application is up to date.  Combined with the "n" option, a batch file could be produced containing the commands necessary to update the application.

i


ignore return status of all commands executed
The "i" option is equivalent to the .IGNORE directive.

k


on error/interrupt:  continue on next target
Make will stop updating targets when a non-zero status is returned by a command.  The "k" option will continue processing targets that do not depend on the target that caused the error.  The .CONTINUE directive in a makefile will enable this error handling capability.

l


the next parameter is the name of a output log file
Make will output an error message when a non-zero status is returned by a command.  The "l" option specifies a file that will record all error messages output by Make during the processing of the makefile.

m


do not search for the MAKEINIT file
The default action for Make is to search for an initialization file called "MAKEINIT" or "TOOLS.INI" if the "ms" option is set.  The "m" option will indicate to Make that processing of the MAKEINIT file is not desired.

ms


Microsoft NMAKE mode
The default action for Make is to process makefiles using Open Watcom syntax rules.  The "ms" option will indicate to Make that it should process makefiles using Microsoft syntax rules.  For example, the line continuation in NMAKE is a backslash ("\") at the end of the line.

n


no execute mode - print commands without executing
The "n" option will print out what commands should be executed to update the application without actually executing them.  Combined with the "h" option, a batch file could be produced which would contain the commands necessary to update the application.

Example:

     wmake /h /n >update.bat
     update

This is useful for applications which require all available resources (memory and devices) for executing the updating commands.

o


use circular implicit rule path
When this option is specified, Make will use a circular path specification search which may save on disk activity for large makefiles.  The "o" option is equivalent to the .OPTIMIZE directive.

p


print out makefile information
The "p" option will cause Make to print out information about all the explicit rules, implicit rules, and macro definitions.

q


query mode - check targets without updating them
The "q" option will cause Make to return a status of 1 if the application requires updating; it will return a status of 0 otherwise.  Here is a example batch file using the "q" option:

Example:

     wmake /q
     if errorstatus 0 goto noupdate
     wmake /q /h /n >\tmp\update.bat
     call \tmp\update.bat
     :noupdate

r


do not use default definitions
The default definitions are:

     
     __MAKEOPTS__ = <options passed to WMAKE>
     __MAKEFILES__ = <list of makefiles>
     __VERSION__ = <version number>
     __LOADDLL__= defined if DLL loading supported
     MAKE = <name of file containing WMAKE>

     # clear .EXTENSIONS list
     .EXTENSIONS:

     # In general,
     # set .EXTENSIONS list as follows
     .EXTENSIONS: .exe .nlm .dsk .lan .exp &
                 .lib .obj &
                 .i &
                 .asm .c .cpp .cxx .cc .for .pas .cob &
                 .h .hpp .hxx .hh .fi .mif .inc

The conditional definitions are:

     
     __DOS__=       for DOS host version
     __MSDOS__=     ...
     __OS2__=       for OS/2 host version
     __RDOS__=      for RDOS host version
     __NT__=        for any Windows NT host version
     __NT386__=     for x86 Windows NT host version
     __NTX64__=     for x64 Windows NT host version
     __NTAXP__=     for Alpha AXP Windows NT host version
     __QNX__=       for QNX host version
     __LINUX__=     for any Linux host version
     __LINUX386__=  for x86 Linux host version
     __LINUXX64__=  for x64 Linux host version
     __LINUXPPC__=  for PowerPC Linux host version
     __LINUXMIPS__= for MIPS Linux host version
     __UNIX__=      for any QNX or Linux host version

For Microsoft NMAKE compatibility (when you use the "ms" option), the following default definitions are established.

     
     # For Microsoft NMAKE compatibility switch,
     # set .EXTENSIONS list as follows
     .EXTENSIONS: .exe .obj .asm .c .cpp .cxx &
                 .bas .cbl .for .f .f90 .pas .res .rc

     %MAKEFLAGS=$(%MAKEFLAGS) $(__MAKEOPTS__)
     MAKE=<name of file containing WMAKE>
     AS=ml
     BC=bc
     CC=cl
     COBOL=cobol
     CPP=cl
     CXX=cl
     FOR=fl
     PASCAL=pl
     RC=rc
     .asm.exe:
         $(AS) $(AFLAGS) $*.asm
     .asm.obj:
         $(AS) $(AFLAGS) /c $*.asm
     .c.exe:
         $(CC) $(CFLAGS) $*.c
     .c.obj:
         $(CC) $(CFLAGS) /c $*.c
     .cpp.exe:
         $(CPP) $(CPPFLAGS) $*.cpp
     .cpp.obj:
         $(CPP) $(CPPFLAGS) /c $*.cpp
     .cxx.exe:
         $(CXX) $(CXXFLAGS) $*.cxx
     .cxx.obj:
         $(CXX) $(CXXFLAGS) $*.cxx
     .bas.obj:
         $(BC) $(BFLAGS) $*.bas
     .cbl.exe:
         $(COBOL) $(COBFLAGS) $*.cbl, $*.exe;
     .cbl.obj:
         $(COBOL) $(COBFLAGS) $*.cbl;
     .f.exe:
         $(FOR) $(FFLAGS) $*.f
     .f.obj:
         $(FOR) /c $(FFLAGS) $*.f
     .f90.exe:
         $(FOR) $(FFLAGS) $*.f90
     .f90.obj:
         $(FOR) /c $(FFLAGS) $*.f90
     .for.exe:
         $(FOR) $(FFLAGS) $*.for
     .for.obj:
         $(FOR) /c $(FFLAGS) $*.for
     .pas.exe:
         $(PASCAL) $(PFLAGS) $*.pas
     .pas.obj:
         $(PASCAL) /c $(PFLAGS) $*.pas
     .rc.res:
         $(RC) $(RFLAGS) /r $*

For UNIX make compatibility (when you use the "u" option), the following default definition is established.

     
     .EXTENSIONS: .exe .obj .c .y .l .f

     %MAKEFLAGS=$(%MAKEFLAGS) $(__MAKEOPTS__)
     MAKE=<name of file containing WMAKE>
     YACC=yacc
     YFLAGS=
     LEX=lex
     LFLAGS=
     LDFLAGS=
     CC=cl
     FC=fl
     .asm.exe:
         $(AS) $(AFLAGS) $*.asm
     .c.exe:
         $(CC) $(CFLAGS) $(LDFLAGS) -o $@ $<
     .f.exe:
         $(FC) $(FFLAGS) $(LDFLAGS) -o $@ $<
     .c.obj:
         $(CC) $(CFLAGS) -c $<
     .f.obj:
         $(FC) $(FFLAGS) -c $<
     .y.obj:
         $(YACC) $(YFLAGS) $<
         $(CC) $(CFLAGS) -c y.tab.c
         del y.tab.c
         move y.tab.obj $@
     .l.obj:
         $(LEX) $(LFLAGS) $<
         $(CC) $(CFLAGS) -c lex.yy.c
         del lex.yy.c
         move lex.yy.obj $@
     .y.c:
         $(YACC) $(YFLAGS) $<
         move y.tab.c $@
     .l.c:
         $(LEX) $(LFLAGS) $<
         move lex.yy.c $@

For POSIX make compatibility (when you use the "ux" option), the following default definition is established.

     
     .EXTENSIONS: .o .obj .c .y .l .a .sh .f

     AR=ar
     ARFLAGS=-rv
     YACC=yacc
     YFLAGS=
     LEX=lex
     LFLAGS=
     LDFLAGS=
     CC=owcc
     CFLAGS=-O
     FC=fort77
     FFLAGS=-O 1
     .c.o:
         $(CC) $(CFLAGS) -c $<
     .f.o:
         $(FC) $(FFLAGS) -c $<
     .y.o:
         $(YACC) $(YFLAGS) $<
         $(CC) $(CFLAGS) -c y.tab.c
         rm -f y.tab.c
         mv y.tab.o $@
     .l.o:
         $(LEX) $(LFLAGS) $<
         $(CC) $(CFLAGS) -c lex.yy.c
         rm -f lex.yy.c
         mv lex.yy.o $@
     .y.c:
         $(YACC) $(YFLAGS) $<
         mv y.tab.c $@
     .l.c:
         $(LEX) $(LFLAGS) $<
         mv lex.yy.c $@
     .c.a:
         $(CC) -c $(CFLAGS) $<
         $(AR) $(ARFLAGS) $@ $*.o
         rm -f $*.o
     .f.a:
         $(FC) -c $(FFLAGS) $<
         $(AR) $(ARFLAGS) $@ $*.o
         rm -f $*.o

The "r" option will disable these definitions before processing any makefiles.

s


silent mode - do not print commands before execution
The "s" option is equivalent to the .SILENT directive.

sn


noisy mode - always print commands before execution
The "sn" option overrules all silencing controls.  It can be used to assist in debugging a makefile.

t


touch files instead of executing commands
Sometimes there are changes which are purely cosmetic (adding a comment to a source file) that will cause targets to be updated needlessly thus wasting computer resources.  The "t" option will make files appear younger without altering their contents.  The "t" option is useful but should be used with caution.

u


UNIX compatibility mode
The "u" option will indicate to Make that the line continuation character should be a backslash "\" rather than an ampersand "&".

v


The "v" option enables a verbose listing of inline temporary files.

y


The "y" option enables the display of a progress line denoting which dependent file has caused a target to be updated.  This is a useful option for helping to debug makefiles.

z


do not erase target after error/interrupt (disables prompting)
The "z" option will indicate to Make that if an error or interrupt occurs during makefile processing then the current target being made should not be deleted.  The .HOLD directive in a makefile has the same effect as the "z" option.

Special Macros


Open Watcom Make has many different special macros.  Here are some of the simpler ones.
Macro
Expansion

$$
represents the character "$"

$#
represents the character "#"

$@
full file name of the target

$*
target with the extension removed

$<
list of all dependents

$?
list of dependents that are younger than the target

The following macros are for more sophisticated makefiles.
Macro
Expansion

__DOS__
This macro is defined in the DOS environment.

__MSDOS__
This macro is defined in the DOS environment.

__RDOS__
This macro is defined in the RDOS environment.

__NT__
This macro is defined in the Windows NT environment.

__OS2__
This macro is defined in the OS/2 environment.

__LINUX__
This macro is defined in the Linux environment.

__QNX__
This macro is defined in the QNX environment.

__UNIX__
This macro is defined in the Linux or QNX environment.

__MAKEOPTS__
contains all of the command line options that WMAKE was invoked with except for any use of the "f" or "n" options.

__MAKEFILES__
contains the names of all of the makefiles processed at the time of expansion (includes the file currently being processed)

MAKE
contains the full name of the file that contains WMAKE

__VERSION__
contains the wmake version.

The next three tables contain macros that are valid during execution of command lists for explicit rules, implicit rules, and the .ERROR directive.  The expansion is presented for the following example:

Example:

     a:\dir\target.ext : b:\dir1\dep1.ex1 c:\dir2\dep2.ex2
Macro
Expansion

$^@
a:\dir\target.ext

$^*
a:\dir\target

$^&
target

$^.
target.ext

$^:
a:\dir\
Macro
Expansion

$[@
b:\dir1\dep1.ex1

$[*
b:\dir1\dep1

$[&
dep1

$[.
dep1.ex1

$[:
b:\dir1\
Macro
Expansion

$]@
c:\dir2\dep2.ex2

$]*
c:\dir2\dep2

$]&
dep2

$].
dep2.ex2

$]:
c:\dir2\

Dependency Declarations


In order for Open Watcom Make to be effective, a list of file dependencies must be declared.  The declarations may be entered into a text file of any name but Make will read a file called "MAKEFILE" by default if it is invoked as follows: 

Example:

     C>wmake

If you want to use a file that is not called "MAKEFILE" then the command line option "f" will cause Make to read the specified file instead of the default "MAKEFILE". 

Example:

     C>wmake /f myfile

We will now go through an example to illustrate how Make may be used for a simple application.  Suppose we have an input file, a report file, and a report generator program then we may declare a dependency as follows: 

     
     #
     # (a comment in a makefile starts with a "#")
     # simple dependency declaration
     #
     balance.lst : ledger.dat
             doreport

Note that the dependency declaration starts at the beginning of a line while commands always have at least one blank or tab before them.  This form of a dependency declaration is called an explicit rule.  The file "BALANCE.LST" is called the target of the rule.  The dependent of the rule is the file "LEDGER.DAT" while "DOREPORT" forms one line of the rule command list.  The dependent is separated from the target by a colon.

Hint:  A good habit to develop is to always put spaces around the colon so that it will not be confused with drive specifications (e.g., a:).

The explicit rule declaration indicates to Make that the program "DOREPORT" should be executed if "LEDGER.DAT" is younger than "BALANCE.LST" or if "BALANCE.LST" does not yet exist.  In general, if the dependent file has a more recent modification date and time than the target file then Open Watcom Make will execute the specified command.  

  Note:  The terminology employed here is used by S.I.Feldman of Bell Laboratories in Make - A Program for Maintaining Computer Programs.  http://www.softlab.ntua.gr/facilities/documentation/unix/docs/make.txt has a copy of this seminal article.  Confusion often arises from the use of the word "dependent".  In this context, it means "a subordinate part".  In the example, "LEDGER.DAT" is a subordinate part of the report "BALANCE.LST".

Multiple Dependents


Suppose that our report "BALANCE.LST" becomes out-of-date if any of the files "LEDGER.DAT", "SALES.DAT" or "PURCHASE.DAT" are modified.  We may modify the dependency rule as follows:

     
     #
     # multiple dependents rule
     #
     balance.lst : ledger.dat sales.dat purchase.dat
             doreport

This is an example of a rule with multiple dependents.  In this situation, the program "DOREPORT" should be executed if any of "LEDGER.DAT", "SALES.DAT" or "PURCHASE.DAT" are younger than "BALANCE.LST" or if "BALANCE.LST" does not yet exist.  In cases where there are multiple dependents, if any of the dependent files has a more recent modification date and time than the target file then Open Watcom Make will execute the specified command.

Multiple Targets


Suppose that the "DOREPORT" program produces two reports.  If both of these reports require updating as a result of modification to the dependent files, we could change the rule as follows:

     
     #
     # multiple targets and multiple dependents rule
     #
     balance.lst summary.lst : ledger.dat sales.dat purchase.dat
             doreport

Suppose that you entered the command:

     
     wmake

which causes Make to start processing the rules described in "MAKEFILE".  In the case where multiple targets are listed in the makefile, Make will, by default, process only the first target it encounters.  In the example, Make will check the date and time of "BALANCE.LST" against its dependents since this is the first target listed.

To indicate that some other target should be processed, the target is specified as an argument to the Make command.

Example:

     wmake summary.lst

There are a number of interesting points to consider:
  1. By default, Make will only check that the target file exists after the command ("DOREPORT" in this example) is executed.  It does not check that the target's time-stamp shows it to be younger.  If the target file does not exist after the command has been executed, an error is reported.
  2. There is no guarantee that the command you have specified does update the target file.  In other words, simply because you have stated a dependency does not mean that one exists.
  3. Furthermore, it is not implied that other targets in our list will not be updated.  In the case of our example, you can assume that we have designed the "doreport" command to update both targets.

Multiple Rules


A makefile may consist of any number of rules.  Note that the following:

     
     target1 target2 : dependent1 dependent2 dependent3
             command list

is equivalent to:

     
     target1 : dependent1 dependent2 dependent3
             command list

     target2 : dependent1 dependent2 dependent3
             command list

Also, the rules may depend on the targets of other rules.

     
     #
     # rule 1: this rule uses rule 2
     #
     balance.lst summary.lst : ledger.dat sales.dat purchase.dat
             doreport

     #
     # rule 2: used by rules 1 and 3
     #
     sales.dat : canada.dat england.dat usa.dat
             dosales

     #
     # rule 3: this rule uses rule 2
     #
     year.lst : ledger.dat sales.dat purchase.dat
             doyearly

The dependents are checked to see if they are the targets of any other rules in the makefile in which case they are updated.  This process of updating dependents that are targets in other rules continues until a rule is reached that has only simple dependents that are not targets of rules.  At this point, if the target does not exist or if any of the dependents is younger than the target then the command list associated with the rule is executed.

Hint:  The term "updating", in this context, refers to the process of checking the time-stamps of dependents and running the specified command list whenever they are out-of-date.  Whenever a dependent is the target of some other rule, the dependent must be brought up-to-date first.  Stated another way, if "A" depends on "B" and "B" depends on "C" and "C" is younger than "B" then we must update "B" before we update "A".

Make will check to ensure that the target exists after its associated command list is executed.  The target existence checking may be disabled in two ways:
  1. use the command line option "c"
  2. use the .NOCHECK directive.

The rule checking returns to the previous rule that had the target as a dependent.  Upon returning to the rule, the command list is executed if the target does not exist or if any of the updated dependents are now younger than the target.   If you were to type:

     
     wmake

here are the steps that would occur with the previous makefile:

     
     update(balance.lst) (rule 1)

       update(ledger.dat)             (not a target)
       update(sales.dat)              (found rule 2)

         update(canada.dat)           (not a target)
         update(england.dat)         (not a target)
         update(usa.dat)              (not a target)
         IF sales.dat does not exist                       OR
            any of (canada.dat,england.dat,usa.dat)
              is younger than sales.dat
         THEN execute "dosales"

       update(purchase.dat)          (not a target)
       IF balance.lst does not exist                       OR
          any of (ledger.dat,sales.dat,purchase.dat)
            is younger than (balance.lst)
       THEN execute "doreport"

The third rule in the makefile will not be included in this update sequence of steps.  Recall that the default target that is "updated" is the first target in the first rule encountered in the makefile.  This is the default action taken by Make when no target is specified on the command line.  If you were to type:

     
     wmake year.lst

then the file "YEAR.LST" would be updated.  As Make reads the rules in "MAKEFILE", it discovers that updating "YEAR.LST" involves updating "SALES.DAT".  The update sequence is similar to the previous example.

Command Lists


A command list is a sequence of one or more commands.  Each command is preceded by one or more spaces or tabs.  Command lists may also be used to construct inline files "on the fly".  Macros substitute in command lists and in inline files.  An inline file is introduced by "<<" in a command in a command list.  Data to insert into that file is placed (left-justified) in the command list.  The data is terminated by "<<" in the first column.  It is not possible to place a line which starts "<<" in an inline file.  More than one inline file may be created in a command.  Data for each is placed in order of reference in the command.

In building the Open Watcom system, it is sometimes necessary to do some text substitution with a program called vi.   This needs a file of instructions.  The following simplifies an example used to build Open Watcom so that inline files may be shown.  Without inline files, this is done as:

     
     $(dllname).imp : $(dllname).lbc ../../trimlbc.vi
         cp $(dllname).lbc $(dllname).imp
         $(vi) -s ../../trimlbc.vi $(dllname).imp

     where trimlbc.vi consists of
     set magic
     set magicstring = ()
     atomic
     %s/\.dll'/'/
     %s/^(\+\+')(.*)('\.'.*')\.[0-9]+$/\1\2\3..'\2'/
     x

A doubled "$" to produce a single dollar is notable when an inline file is used:

     
     $(dllname).imp : $(dllname).lbc
         cp $(dllname).lbc $(dllname).imp
         $(vi) -s << $(dllname).imp
     set magic
     set magicstring = ()
     atomic
     %s/\.dll'/'/
     %s/^(\+\+')(.*)('\.'.*')\.[0-9]+$$/\1\2\3..'\2'/
     x
     <<

A filename may follow a "<<" on a command line to cause a file with that name to be created.  (Otherwise, 'WMAKE' chooses a name.) "keep" or "nokeep" may follow a terminating "<<" to show what to do with the file after usage.  The default is "nokeep" which zaps it.

Final Commands (.AFTER)


The .AFTER directive specifies commands for Make to run after it has done all other commands.  See the section entitled Command List Directives for a full description of its use.

Ignoring Dependent Timestamps (.ALWAYS)


The .ALWAYS directive indicates to Make that the target should always be updated regardless of the timestamps of its dependents.

     
     #
     # .always directive
     #

     foo : bar .always
         wtouch $@

foo is updated each time Make is run.

Automatic Dependency Detection (.AUTODEPEND)


Explicit listing of dependencies in a makefile can often be tedious in the development and maintenance phases of a project.   The Open Watcom C/C++ compiler will insert dependency information into the object file as it processes source files so that a complete snapshot of the files necessary to build the object file are recorded.  Since all files do not have dependency information contained within them in a standard form, it is necessary to indicate to Make when dependencies are present.

To illustrate the use of the .AUTODEPEND directive, we will show its use in an implicit rule and in an explicit rule.

     
     #
     # .AUTODEPEND example
     #
     .c.obj: .AUTODEPEND
             wcc386 $[* $(compile_options)

     test.exe : a.obj b.obj c.obj test.res
             wlink FILE a.obj, b.obj, c.obj
             wrc -q -bt=windows test.res test.exe

     test.res : test.rc test.ico .AUTODEPEND
             wrc -ad -q -bt=windows -r $[@ $^@

In the above example, Make will use the contents of the object file to determine whether the object file has to be built during processing.  The Open Watcom Resource Compiler can also insert dependency information into a resource file that can be used by Make.

Initial Commands (.BEFORE)


The .BEFORE directive specifies commands for Make to run before it does any other command.  See the section entitled Command List Directives for a full description of its use.

Disable Implicit Rules (.BLOCK)


The .BLOCK directive and the "b" command line option are alternative controls to cause implicit rules to be ignored.  See the section entitled Command Line Options for a full description of its use.

Ignoring Errors (.CONTINUE)


The .CONTINUE directive and the "b" command line option are alternative controls to cause failing commands to be ignored.  See the section entitled Command Line Options for a full description of its use.

     
     #
     # .continue example
     #

     .continue

     all: bad good
         @%null

     bad:
         false

     good:
         touch $@

Although the command list for bad fails, that for good is done.  Without the directive, good is not built.

Default Command List (.DEFAULT)


The .DEFAULT directive provides a default command list for those targets which lack one.  See the section entitled Command List Directives for a full description of its use.

     
     #
     # .default example
     #

     .default
         @echo Using default rule to update target "$@"
         @echo because of dependent(s) "$<"
         wtouch $@

     all: foo

     foo:
         wtouch foo

"all" has no command list.  The one supplied to the default directive is executed instead.

Erasing Targets After Error (.ERASE)


Most operating system utilities and programs have special return codes that indicate error conditions.  Open Watcom Make will check the return code for every command executed.  If the return code is non-zero, Make will stop processing the current rule and optionally delete the current target being updated.  By default, Make will prompt for deletion of the current target.  The .ERASE directive indicates to Make that the target should be deleted if an error occurs during the execution of the associated command list.  No prompt is issued in this case.  Here is an example of the .ERASE directive:

     
     #
     # .ERASE example
     #
     .ERASE
     balance.lst : ledger.dat sales.dat purchase.dat
             doreport

If the program "DOREPORT" executes and its return code is non-zero then Make will attempt to delete "BALANCE.LST".

Error Action (.ERROR)


The .ERROR directive supplies a command list for error conditions.  See the section entitled Command List Directives for a full description of its use.

     
     #
     # .error example
     #

     .error:
             @echo it is good that "$@" is known

     all : .symbolic
             false

Ignoring Target Timestamp (.EXISTSONLY)


The .EXISTSONLY directive indicates to Make that the target should not be updated if it already exists, regardless of its timestamp.

     
     #
     # .existsonly directive
     #

     foo: .existsonly
             wtouch $@

If absent, this file creates foo; if present, this file does nothing.

Specifying Explicitly Updated Targets (.EXPLICIT)


The .EXPLICIT directive may me used to specify a target that needs to be explicitly updated.  Normally, the first target in a makefule will be implicitly updated if no target is specified on Make command line.  The .EXPLICIT directive prevents this, and is useful for instance when creating files designed to be included for other make files.

     
     #
     # .EXPLICIT example
     #
     target : .symbolic .explicit
             @echo updating first target

     next : .symbolic
             @echo updating next target

In the above example, Make will not automatically update "target", despite the fact that it is the first one listed.

Defining Recognized File Extensions (.EXTENSIONS)


The .EXTENSIONS directive and its synonym, the .SUFFIXES directive declare which extensions are allowed to be used in implicit rules and how these extensions are ordered.  .EXTENSIONS is the traditional Watcom name; .SUFFIXES is the corresponding POSIX name.  The default .EXTENSIONS declaration is:

     
     .EXTENSIONS:
     .EXTENSIONS: .exe .nlm .dsk .lan .exp .lib .obj &
                  .i .asm .c .cpp .cxx .cc .for .pas .cob &
                  .h .hpp .hxx .hh .fi .mif .inc

A .EXTENSIONS directive with an empty list will clear the .EXTENSIONS list and any previously defined implicit rules.  Any subsequent .EXTENSIONS directives will add extensions to the end of the list.

Hint:  The default .EXTENSIONS declaration could have been coded as:

.EXTENSIONS:

.EXTENSIONS:  .exe
.EXTENSIONS:  .nlm .dsk .lan .exp
.EXTENSIONS:  .lib
.EXTENSIONS:  .obj
.EXTENSIONS:  .i .asm .c .cpp .cxx .cc
.EXTENSIONS:  .for .pas .cob
.EXTENSIONS:  .h .hpp .hxx .hh .fi .mif .inc
.EXTENSIONS:  .inc
with identical results.

Make will not allow any implicit rule declarations that use extensions that are not in the current .EXTENSIONS list.

     
     #
     # .extensions and .suffixes directives
     #

     .suffixes : # Clear list
     .extensions : .foo .bar

     .bar.foo:
         copy $< $@

     fubar.foo:

     fubar.bar: .existsonly
         wtouch $@

The first time this example runs, Make creates fubar.foo.  This example always ensures that fubar.foo is a copy of fubar.bar.  Note the implicit connection beween the two files.

Approximate Timestamp Matching (.FUZZY)


The .FUZZY directive allows .AUTODEPEND times to be out by a minute without considering a target out of date.  It is only useful in conjunction with the .JUST_ENOUGH directive when Make is calculating the timestamp to set the target to.

Preserving Targets After Error (.HOLD)


Most operating system utilities and programs have special return codes that indicate error conditions.  Open Watcom Make will check the return code for every command executed.  If the return code is non-zero, Make will stop processing the current rule and optionally delete the current target being updated.  By default, Make will prompt for deletion of the current target.  The .HOLD directive indicates to Make that the target should not be deleted if an error occurs during the execution of the associated command list.  No prompt is issued in this case.  The .HOLD directive is similar to .PRECIOUS but applies to all targets listed in the makefile.  Here is an example of the .HOLD directive:

     
     #
     # .HOLD example
     #
     .HOLD
     balance.lst : ledger.dat sales.dat purchase.dat
             doreport

If the program "DOREPORT" executes and its return code is non-zero then Make will not delete "BALANCE.LST".

Ignoring Return Codes (.IGNORE)


Some programs do not have meaningful return codes so for these programs we want to ignore the return code completely.   There are different ways to ignore return codes namely,
  1. use the command line option "i"
  2. put a "-" in front of specific commands, or
  3. use the .IGNORE directive.

In the following example, the rule:

     
     #
     # ignore return code example
     #
     balance.lst : ledger.dat sales.dat purchase.dat
             -doreport

will ignore the return status from the program "DOREPORT".  Using the dash in front of the command is the preferred method for ignoring return codes because it allows Make to check all the other return codes.

The .IGNORE directive is used as follows:

     
     #
     # .IGNORE example
     #
     .IGNORE
     balance.lst : ledger.dat sales.dat purchase.dat
             doreport

Using the .IGNORE directive will cause Make to ignore the return code for every command.  The "i" command line option and the .IGNORE directive prohibit Make from performing any error checking on the commands executed and, as such, should be used with caution.

Another way to handle non-zero return codes is to continue processing targets which do not depend on the target that had a non-zero return code during execution of its associated command list.  There are two ways of indicating to Make that processing should continue after a non-zero return code:
  1. use the command line option "k"
  2. use the .CONTINUE directive.

Minimising Target Timestamp (.JUST_ENOUGH)


The .JUST_ENOUGH directive is equivalent to the "j" command line option.  The timestamps of created targets are set to be the same as those of their youngest dependendents.

     
     #
     # .JUST_ENOUGH example
     #

     .just_enough

     .c.exe:
             wcl386 -zq $<

     hello.exe:

hello.exe is given the same timestamp as hello.c, and not the usual timestamp corresponding to when hello.exe was built.

Updating Targets Multiple Times (.MULTIPLE)


The .MULTIPLE directive is used to update a target multiple times.  Normally, Make will only update each target once while processing a makefile.  The .MULTIPLE directive is useful if a target needs to be updated more than once, for instance in case the target is destroyed during processing of other targets.  Consider the following example:

     
     #
     # example not using .multiple
     #

     all: targ1 targ2

     target:
             wtouch target

     targ1: target
             rm target
             wtouch targ1

     targ2: target
             rm target
             wtouch targ2

This makefile will fail because "target" is destroyed when updating "targ1", and later is implicitly expected to exist when updating "targ2".  Using the .MULTIPLE directive will work around this problem:

     
     #
     # .MULTIPLE example
     #

     all : targ1 targ2

     target : .multiple
             wtouch target

     targ1 : target
             rm target
             wtouch targ1

     targ2 : target
             rm target
             wtouch targ2

Now Make will attempt to update "target" again when updating "targ2", discover that "target" doesn't exist, and recreate it.

Ignoring Target Timestamp (.NOCHECK)


The .NOCHECK directive is used to disable target existence checks in a makefile.  See the section entitled Command Line Options for a full description of its use.

Cache Search Path (.OPTIMIZE)


The .OPTIMIZE directive and the equivalent "o" command line option cause Make to use a circular path search.  If a file is found in a particular directory, that directory will be the first searched for the next file.   See the section entitled Command Line Options for a full description of its use.

Preserving Targets (.PRECIOUS)


Most operating system utilities and programs have special return codes that indicate error conditions.  Open Watcom Make will check the return code for every command executed.  If the return code is non-zero, Make will stop processing the current rule and optionally delete the current target being updated.  If a file is precious enough that this treatment of return codes is not wanted then the .PRECIOUS directive may be used.  The .PRECIOUS directive indicates to Make that the target should not be deleted if an error occurs during the execution of the associated command list.  Here is an example of the .PRECIOUS directive:

     
     #
     # .PRECIOUS example
     #
     balance summary : sales.dat purchase.dat .PRECIOUS
             doreport

If the program "DOREPORT" executes and its return code is non-zero then Make will not attempt to delete "BALANCE" or "SUMMARY".  If only one of the files is precious then the makefile could be coded as follows:

     
     #
     # .PRECIOUS example
     #
     balance : .PRECIOUS
     balance summary : sales.dat purchase.dat
             doreport

The file "BALANCE.LST" will not be deleted if an error occurs while the program "DOREPORT" is executing.

Name Command Sequence (.PROCEDURE)


The .PROCEDURE directive may be used to construct "procedures" in a makefile.

     
     #
     # .procedure example
     #

     all: .symbolic
         @%make proc

     proc: .procedure
         @echo Executing procedure "proc"

Re-Checking Target Timestamp (.RECHECK)


Make will re-check the target's timestamp, rather than assuming it was updated by its command list.  This is useful if the target is built by another make- style tool, as in the following example:

     
     #
     # .RECHECK example
     #
     foo.gz : foo
             gzip foo

     foo : .ALWAYS .RECHECK
             nant -buildfile:foo.build

foo's command list will always be run, but foo will only be compressed if the timestamp is actually changed.

Suppressing Terminal Output (.SILENT)


As commands are executed, Open Watcom Make will print out the current command before it is executed.  It is possible to execute the makefile without having the commands printed.  There are three ways to inhibit the printing of the commands before they are executed, namely:
  1. use the command line option "s"
  2. put an "@" in front of specific commands, or
  3. use the .SILENT directive.

In the following example, the rule:

     
     #
     # silent command example
     #
     balance summary : ledger.dat sales.dat purchase.dat
             @doreport

will prevent the string "doreport" from being printed on the screen before the command is executed.

The .SILENT directive is used as follows:

     
     #
     # .SILENT example
     #
     .SILENT
     balance summary : ledger.dat sales.dat purchase.dat
             doreport

Using the .SILENT directive or the "s" command line option will inhibit the printing of all commands before they are executed.  The "sn" command line option can be used to veto any silencing control.

At this point, most of the capability of Make may be realized.  Methods for making makefiles more succinct will be discussed.

Defining Recognized File Extensions (.SUFFIXES)


The .SUFFIXES directive declares which extensions are allowed to be used in implicit rules and how these extensions are ordered.  It is a synonym for the .EXTENSIONS directive.  See the section entitled Defining Recognized File Extensions (.EXTENSIONS) for a full description of both directives.

Targets Without Any Dependents (.SYMBOLIC)


There must always be at least one target in a rule but it is not necessary to have any dependents.  If a target does not have any dependents, the command list associated with the rule will always be executed if the target is updated.

You might ask, "What may a rule with no dependents be used for?".  A rule with no dependents may be used to describe actions that are useful for the group of files being maintained.  Possible uses include backing up files, cleaning up files, or printing files.

To illustrate the use of the .SYMBOLIC directive, we will add two new rules to the previous example.  First, we will omit the .SYMBOLIC directive and observe what will happen when it is not present.

     
     #
     # rule 4: backup the data files
     #
     backup :
             echo "insert backup disk"
             pause
             copy *.dat a:
             echo "backup complete"

     #
     # rule 5: cleanup temporary files
     #
     cleanup :
             del *.tmp
             del \tmp\*.*

and then execute the command:

     
     wmake backup

Make will execute the command list associated with the "backup" target and issue an error message indicating that the file "BACKUP" does not exist after the command list was executed.  The same thing would happen if we typed:

     
     wmake cleanup

In this makefile we are using "backup" and "cleanup" to represent actions we want performed.  The names are not real files but rather they are symbolic names.  This special type of target may be declared with the .SYMBOLIC directive.  This time, we show rules 4 and 5 with the appropriate addition of .SYMBOLIC directives.

     
     #
     # rule 4: backup the data files
     #
     backup : .SYMBOLIC
             echo "insert backup disk"
             pause
             copy *.dat a:
             echo "backup complete"

     #
     # rule 5: cleanup temporary files
     #
     cleanup : .SYMBOLIC
             del *.tmp
             del \tmp\*.*

The use of the .SYMBOLIC directive indicates to Make that the target should always be updated internally after the command list associated with the rule has been executed.  A short form for the common idiom of singular .SYMBOLIC targets like:

     
     target : .SYMBOLIC
             commands

is:

     
     target
             commands

This kind of target definition is useful for many types of management tasks that can be described in a makefile.

Macros


Open Watcom Make has a simple macro facility that may be used to improve makefiles by making them easier to read and maintain.   A macro identifier may be composed from a string of alphabetic characters and numeric characters.  The underscore character is also allowed in a macro identifier.  If the macro identifier starts with a "%" character, the macro identifier represents an environment variable.  For instance, the macro identifier "%path" represents the environment variable "path".
Macro identifiers
Valid?

2morrow
yes

stitch_in_9
yes

invalid~id
no

2b_or_not_2b
yes

%path
yes

reports
yes

!@#*%
no

We will use a programming example to show how macros are used.  The programming example involves four C/C++ source files and two header files.  Here is the initial makefile (before macros):

     
     #
     # programming example
     # (before macros)
     #
     plot.exe : main.obj input.obj calc.obj output.obj
             wlink @plot

     main.obj : main.c defs.h globals.h
             wcc386 main /mf /d1 /w3

     calc.obj : calc.c defs.h globals.h
             wcc386 calc /mf /d1 /w3

     input.obj : input.c defs.h globals.h
             wcc386 input /mf /d1 /w3

     output.obj : output.c defs.h globals.h
             wcc386 output /mf /d1 /w3

Macros become useful when changes must be made to makefiles.  If the programmer wanted to change the compiler options for the different compiles, the programmer would have to make a global change to the makefile.  With this simple example, it is quite easy to make the change but try to imagine a more complex example with different programs having similar options.  The global change made by the editor could cause problems by changing the options for other programs.  A good habit to develop is to define macros for any programs that have command line options.  In our example, we would change the makefile to be:

     
     #
     # programming example
     # (after macros)
     #
     link_options =
     compiler = wcc386
     compile_options = /mf /d1 /w3

     plot.exe : main.obj input.obj calc.obj output.obj
             wlink $(link_options) @plot

     main.obj : main.c defs.h globals.h
             $(compiler) main $(compile_options)

     calc.obj : calc.c defs.h globals.h
             $(compiler) calc $(compile_options)

     input.obj : input.c defs.h globals.h
             $(compiler) input $(compile_options)

     output.obj : output.c defs.h globals.h
             $(compiler) output $(compile_options)

A macro definition consists of a macro identifier starting on the beginning of the line followed by an "=" which in turn is followed by the text to be replaced.  A macro may be redefined, with the latest declaration being used for subsequent expansions (no warning is given upon redefinition of a macro).  The replacement text may contain macro references.

A macro reference may occur in two forms.  The previous example illustrates one way to reference macros whereby the macro identifier is delimited by "$(" and ")".  The parentheses are optional so the macros "compiler" and "compile_options" could be referenced by:

     
     main.obj : main.c defs.h globals.h
             $compiler main $compile_options

Certain ambiguities may arise with this form of macro reference.  For instance, examine this makefile fragment:

Example:

     temporary_dir = \tmp\
     temporary_file = $temporary_dirtmp000.tmp

The intention of the declarations is to have a macro that will expand into a file specification for a temporary file.   Make will collect the largest identifier possible before macro expansion occurs.  The macro reference is followed by text that looks like part of the macro identifier ("tmp000") so the macro identifier that will be referenced will be "temporary_dirtmp000".  The incorrect macro identifier will not be defined so an error message will be issued.

If the makefile fragment was:

     
     temporary_dir = \tmp\
     temporary_file = $(temporary_dir)tmp000.tmp

there would be no ambiguity.  The preferred way to reference macros is to enclose the macro identifier by "$(" and ")".

Macro references are expanded immediately on dependency lines (and thus may not contain references to macros that have not been defined) but other macro references have their expansion deferred until they are used in a command.  In the previous example, the macros "link_options", "compiler", and "compile_options" will not be expanded until the commands that reference them are executed.

Another use for macros is to replace large amounts of text with a much smaller macro reference.  In our example, we only have two header files but suppose we had very many header files.  Each explicit rule would be very large and difficult to read and maintain.  We will use the previous example makefile to illustrate this use of macros.

     
     #
     # programming example
     # (with more macros)
     #
     link_options =
     compiler = wcc386
     compile_options = /mf /d1 /w3

     header_files = defs.h globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             wlink $(link_options) @plot

     main.obj : main.c $(header_files)
             $(compiler) main $(compile_options)

     calc.obj : calc.c $(header_files)
             $(compiler) calc $(compile_options)

     input.obj : input.c $(header_files)
             $(compiler) input $(compile_options)

     output.obj : output.c $(header_files)
             $(compiler) output $(compile_options)

Notice the ampersand ("&") at the end of the macro definition for "object_files".  The ampersand indicates that the macro definition continues on the next line.  In general, if you want to continue a line in a makefile, use an ampersand ("&") at the end of the line.

There are special macros provided by Make to access environment variable names.  To access the PATH environment variable in a makefile, we use the macro identifier "%path".  For example, if we have the following line in a command list:

Example:

           echo $(%path)

it will print out the current value of the PATH environment variable when it is executed.

There are two other special environment macros that are predefined by Make.  The macro identifier "%cdrive" will expand into one letter representing the current drive.  Note that it is operating system dependent whether the cd command changes the current drive.  The macro identifier "%cwd" will expand into the current working directory.   These macro identifiers are not very useful unless we can specify that they be expanded immediately.  The complementary macros "$+" and "$-" respectively turn on and turn off immediate expansion of macros.  The scope of the "$+" macro is the current line after which the default macro expansion behaviour is resumed.  A possible use of these macros is illustrated by the following example makefile. 

     
     #
     # $(%cdrive), $(%cwd), $+, and $- example
     #
     dir1 = $(%cdrive):$(%cwd)
     dir2 = $+ $(dir1) $-
     example : .SYMBOLIC
             cd ..
             echo $(dir1)
             echo $(dir2)

Which would produce the following output if the current working directory is C:\WATCOM\SOURCE\EXAMPLE:

Example:

     (command output only)
     C:\WATCOM\SOURCE
     C:\WATCOM\SOURCE\EXAMPLE

The macro definition for "dir2" forces immediate expansion of the "%cdrive" and "%cwd" macros thus defining "dir2" to be the current directory that Make was invoked in.  The macro "dir1" is not expanded until execution time when the current directory has changed from the initial directory.

Combining the $+ and $- special macros with the special macro identifiers "%cdrive" and "%cwd" is a useful makefile technique.  The $+ and $- special macros are general enough to be used in many different ways.

Constructing other macros is another use for the $+ and $- special macros.  Make allows macros to be redefined and combining this with the $+ and $- special macros, similar looking macros may be constructed. 

     
     #
     # macro construction with $+ and $-
     #
     template = file1.$(ext) file2.$(ext) file3.$(ext) file4.$(ext)
     ext = dat
     data_files = $+ $(template) $-
     ext = lst
     listing_files = $+ $(template) $-

     example : .SYMBOLIC
             echo $(data_files)
             echo $(listing_files)

This makefile would produce the following output:
Example:

     file1.dat file2.dat file3.dat file4.dat
     file1.lst file2.lst file3.lst file4.lst

Adding more text to a macro can also be done with the $+ and $- special macros. 

     
     #
     # macro addition with $+ and $-
     #
     objs = file1.obj file2.obj file3.obj
     objs = $+$(objs)$- file4.obj
     objs = $+$(objs)$- file5.obj

     example : .SYMBOLIC
             echo $(objs)

This makefile would produce the following output:

Example:

     file1.obj file2.obj file3.obj file4.obj file5.obj

Make provides a shorthand notation for this type of macro operation.  Text can be added to a macro by using the "+=" macro assignment.  The previous makefile can be written as: 

     
     #
     # macro addition with +=
     #
     objs  = file1.obj file2.obj file3.obj
     objs += file4.obj
     objs += file5.obj

     example : .SYMBOLIC
             echo $(objs)

and still produce the same results.  The shorthand notation "+=" supported by Make provides a quick way to add more text to macros.

Make provides the "!inject" preprocessor directive to append a "word" (one or more graphic characters) to one or more macros.  The previous makefile is adapted to show the usage: 

     
     #
     # macro construction with !inject
     #
     !inject file1.obj objs objs12 objs13 objs14 objs15
     !inject file2.obj objs objs12 objs13 objs14 objs15
     !inject file3.obj objs        objs13 objs14 objs15
     !inject file4.obj objs                objs14 objs15
     !inject file5.obj objs                       objs15

     example : .SYMBOLIC
             echo $(objs)
             echo $(objs12)
             echo $(objs13)
             echo $(objs14)
             echo $(objs15)

This makefile would produce the following output:

Example:

     file1.obj file2.obj file3.obj file4.obj file5.obj
     file1.obj file2.obj
     file1.obj file2.obj file3.obj
     file1.obj file2.obj file3.obj file4.obj
     file1.obj file2.obj file3.obj file4.obj file5.obj

The "!inject" preprocessor directive supported by Make provides a way to append a word to several macros.

There are instances when it is useful to have macro identifiers that have macro references contained in them.  If you wanted to print out an informative message before linking the executable that was different between the debugging and production version, we would express it as follows: 

     
     #
     # programming example
     # (macro selection)
     #
     version = debugging          # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = defs.h globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @plot

     main.obj : main.c $(header_files)
             $(compiler) main $(compile_options)

     calc.obj : calc.c $(header_files)
             $(compiler) calc $(compile_options)

     input.obj : input.c $(header_files)
             $(compiler) input $(compile_options)

     output.obj : output.c $(header_files)
             $(compiler) output $(compile_options)

Take notice of the macro references that are of the form:

     
     $(<partial_macro_identifier>$(version))

The expansion of a macro reference begins by expanding any macros seen until a matching right parenthesis is found.   The macro identifier that is present after the matching parenthesis is found will be expanded.  The other form of macro reference namely:

     
     $<macro_identifier>

may be used in a similar fashion.  The previous example would be of the form:

     
     $<partial_macro_identifier>$version

Macro expansion occurs until a character that cannot be in a macro identifier is found (on the same line as the "$") after which the resultant macro identifier is expanded.  If you want two macros to be concatenated then the line would have to be coded:

     
     $(macro1)$(macro2)

The use of parentheses is the preferred method for macro references because it completely specifies the order of expansion.

In the previous example, we can see that the four command lines that invoke the compiler are very similar in form.   We may make use of these similarities by denoting the command by a macro reference.  We need to be able to define a macro that will expand into the correct command when processed.  Fortunately, Make can reference the first member of the dependent list, the last member of the dependent list, and the current target being updated with the use of some special macros.  These special macros have the form: 

     
     $<file_specifier><form_qualifier>

where <file_specifier> is one of:
"^"
represents the current target being updated

"["
represents the first member of the dependent list

"]"
represents the last member of the dependent list

and <form_qualifier> is one of:
"@"
full file name

"*"
file name with extension removed

"&"
file name with path and extension removed

"."
file name with path removed

":"
path of file name

If the file "D:\DIR1\DIR2\NAME.EXT" is the current target being updated then the following example will show how the form qualifiers are used.
Macro
Expansion for D:\DIR1\DIR2\NAME.EXT

$^@
D:\DIR1\DIR2\NAME.EXT

$^*
D:\DIR1\DIR2\NAME

$^&
NAME

$^.
NAME.EXT

$^:
D:\DIR1\DIR2\

These special macros provide the capability to reference targets and dependents in a variety of ways.
     
     #
     # programming example
     # (more macros)
     #
     version = debugging          # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     compiler_command = wcc386 $[* $(compile_options)

     header_files = defs.h globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     main.obj : main.c $(header_files)
             $(compiler_command)

     calc.obj : calc.c $(header_files)
             $(compiler_command)

     input.obj : input.c $(header_files)
             $(compiler_command)

     output.obj : output.c $(header_files)
             $(compiler_command)

This example illustrates the use of the special dependency macros.  Notice the use of "$^*" in the linker command.  The macro expands into the string "plot" since "plot.exe" is the target when the command is processed.  The use of the special dependency macros is recommended because they make use of information that is already contained in the dependency rule.

At this point, we know that macro references begin with a "$" and that comments begin with a "#".   What happens if we want to use these characters without their special meaning?  Make has two special macros that provide these characters to you.  The special macro "$$" will result in a "$" when expanded and "$#" will expand into a "#".  These special macros are provided so that you are not forced to work around the special meanings of the "$" and "#" characters.

There is also a simple macro text substitution facility.  We have previously seen that a macro call can be made with $(macroname).  The construct $(macroname:string1=string2) substitutes macroname with each occurrence of string1 replaced by string2.  We have already seen that it can be useful for a macro to be a set of object file names separated by spaces.  The file directive in wlink can accept a set of names separated by commas.

     
     #
     # programming example
     # (macro substitution)
     #

     .c.obj:
             wcc386 -zq $*.c

     object_files = main.obj input.obj calc.obj output.obj

     plot.exe : $(object_files)
             wlink name $@ file $(object_files: =,)

Note that macro substitution cannot be used with special macros.

It is also worth noting that although the above example shows a valid approach, the same problem, that is, providing a list of object files to wlink, can be solved without macro subsitutions.  The solution is using the {} syntax of wlink, as shown in the following example.  Refer to the Open Watcom Linker Guide for details.

     
     #
     # programming example
     # (not using macro substitution)
     #

     .c.obj:
             wcc386 -zq $*.c

     object_files = main.obj input.obj calc.obj output.obj

     plot.exe : $(object_files)
             wlink name $@ file { $(object_files) }

Implicit Rules


Open Watcom Make is capable of accepting declarations of commonly used dependencies.  These declarations are called "implicit rules" as opposed to "explicit rules" which were discussed previously.  Implicit rules may be applied only in instances where you are able to describe a dependency in terms of file extensions.

Hint:  Recall that a file extension is the portion of the file name which follows the period.  In the file specification:

c:\dos\ansi.sys

the file extension is "SYS".

An implicit rule provides a command list for a dependency between files with certain extensions.  The form of an implicit rule is as follows:

     
     .<dependent_extension>.<target_extension>:
             <command_list>

Implicit rules are used if a file has not been declared as a target in any explicit rule or the file has been declared as a target in an explicit rule with no command list.  For a given target file, a search is conducted to see if there are any implicit rules defined for the target file's extension in which case Make will then check if the file with the dependent extension in the implicit rule exists.  If the file with the dependent extension exists then the command list associated with the implicit rule is executed and processing of the makefile continues.

Other implicit rules for the target extension are searched in a similar fashion.  The order in which the dependent extensions are checked becomes important if there is more than one implicit rule declaration for a target extension.  If we have the following makefile fragment:

Example:

     .pas.obj:
             (command list)
     .c.obj:
             (command list)

an ambiguity arises.  If we have a target file "TEST.OBJ" then which do we check for first, "TEST.PAS" or "TEST.C"?  Make handles this with the previously described .EXTENSIONS directive.  Returning to our makefile fragment:

     
     .pas.obj:
             (command list)
     .c.obj:
             (command list)

and our target file "TEST.OBJ", we know that the .EXTENSIONS list determines in what order the dependents "TEST.PAS" and "TEST.C" will be tried.  If the .EXTENSIONS declaration is:

Example:

     .EXTENSIONS:
     .EXTENSIONS: .exe .obj .asm .pas .c .cpp .for .cob

we can see that the dependent file "TEST.PAS" will be tried first as a possible dependent with "TEST.C" being tried next.

One apparent problem with implicit rules and their associated command lists is that they are used for many different targets and dependents during the processing of a makefile.  The same problem occurs with commands constructed from macros.  Recall that there is a set of special macros that start with "$^", "$[", or "$]" that reference the target, first dependent, or last dependent of an explicit dependency rule.  In an implicit rule there may be only one dependent or many dependents depending on whether the rule is being executed for a target with a single colon ":" or double colon "::" dependency.  If the target has a single colon or double colon dependency, the "$^", "$[", and "$]" special macros will reflect the values in the rule that caused the implicit rule to be invoked.  Otherwise, if the target does not have a dependency rule then the "$[" and "$]" special macros will be set to the same value, namely, the file found in the implicit rule search.

We will use the last programming example to illustrate a possible use of implicit rules.

     
     #
     # programming example
     # (implicit rules)
     #
     version = debugging          # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = defs.h globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c.obj:
             $(compiler) $[* $(compile_options)

     main.obj : main.c $(header_files)

     calc.obj : calc.c $(header_files)

     input.obj : input.c $(header_files)

     output.obj : output.c $(header_files)

As this makefile is processed, any time an object file is found to be older than its associated source file or header files then Make will attempt to execute the command list associated with the explicit rule.  Since there are no command lists associated with the four object file targets, an implicit rule search is conducted.  Suppose "CALC.OBJ" was older than "CALC.C".  The lack of a command list in the explicit rule with "CALC.OBJ" as a target causes the ".c.obj" implicit rule to be invoked for "CALC.OBJ".  The file "CALC.C" is found to exist so the commands

     
             wcc386 calc /mf /d1 /w3
             echo linking debug version ...
             wlink debug all @plot

are executed.  The last two commands are a result of the compilation of "CALC.C" producing a "CALC.OBJ" file that is younger than the "PLOT.EXE" file that in turn must be generated again.

The use of implicit rules is straightforward when all the files that the makefile deals with are in the current directory.   Larger applications may have files that are in many different directories.  Suppose we moved the programming example files to three sub-directories.
Files
Sub-directory

*.H
\EXAMPLE\H

*.C
\EXAMPLE\C

rest
\EXAMPLE\O

Now the previous makefile (located in the \EXAMPLE\O sub-directory) would look like this:

     
     #
     # programming example
     # (implicit rules)
     #
     h_dir   = \example\h\ #sub-directory containing header files
     c_dir   = \example\c\ #sub-directory containing C/C++ files
     version = debugging   # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = $(h_dir)defs.h $(h_dir)globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c.obj:
             $(compiler) $[* $(compile_options)

     main.obj : $(c_dir)main.c $(header_files)

     calc.obj : $(c_dir)calc.c $(header_files)

     input.obj : $(c_dir)input.c $(header_files)

     output.obj : $(c_dir)output.c $(header_files)

Suppose "\EXAMPLE\O\CALC.OBJ" was older than "\EXAMPLE\C\CALC.C".  The lack of a command list in the explicit rule with "CALC.OBJ" as a target causes the ".c.obj" implicit rule to be invoked for "CALC.OBJ".  At this time, the file "\EXAMPLE\O\CALC.C" is not found so an error is reported indicating that "CALC.OBJ" could not be updated.  How may implicit rules be useful in larger applications if they will only search the current directory for the dependent file?  We must specify more information about the dependent extension (in this case ".C").  We do this by associating a path with the dependent extension as follows:  

     
     .<dependent_extension> : <path_specification>

This allows the implicit rule search to find the files with the dependent extension.

Hint:  A valid path specification is made up of directory specifications separated by semicolons (";").  Here are some path specifications:

D:;C:\DOS;C:\UTILS;C:\WC
C:\SYS
A:\BIN;D:
Notice that these path specifications are identical to the form required by the operating system shell's "PATH" command.

Our makefile will be correct now if we add the new declaration as follows:

     
     #
     # programming example
     # (implicit rules)
     #
     h_dir   = \example\h\ #sub-directory containing header files
     c_dir   = \example\c\ #sub-directory containing C/C++ files
     version = debugging    # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))
     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = $(h_dir)defs.h $(h_dir)globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c:     $(c_dir)
     .c.obj:
             $(compiler) $[* $(compile_options)

     main.obj : $(c_dir)main.c $(header_files)

     calc.obj : $(c_dir)calc.c $(header_files)

     input.obj : $(c_dir)input.c $(header_files)

     output.obj : $(c_dir)output.c $(header_files)

Suppose "\EXAMPLE\O\CALC.OBJ" is older than "\EXAMPLE\C\CALC.C".  The lack of a command list in the explicit rule with "CALC.OBJ" as a target will cause the ".c.obj" implicit rule to be invoked for "CALC.OBJ".  The dependent extension ".C" has a path associated with it so the file "\EXAMPLE\C\CALC.C" is found to exist.  The commands

     
             wcc386 \EXAMPLE\C\CALC /mf /d1 /w3
             echo linking debug version ...
             wlink debug all @plot

are executed to update the necessary files.

If the application requires many source files in different directories Make will search for the files using their associated path specifications.  For instance, if the current example files were setup as follows:
Sub-directory
Contents

\EXAMPLE\H
DEFS.H, GLOBALS.H

\EXAMPLE\C\PROGRAM
MAIN.C, CALC.C

\EXAMPLE\C\SCREEN
INPUT.C, OUTPUT.C

\EXAMPLE\O
PLOT.EXE, MAKEFILE, MAIN.OBJ, CALC.OBJ, INPUT.OBJ, OUTPUT.OBJ

the makefile would be changed to:

     
     #
     # programming example
     # (implicit rules)
     #
     h_dir        = ..\h\    # sub-directory with header files
                              # sub-directories with C/C++ source files
     program_dir  = ..\c\program\ # - MAIN.C, CALC.C
     screen_dir   = ..\c\screen\  # - INPUT.C, OUTPUT.C
     version      = debugging     # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = $(h_dir)defs.h $(h_dir)globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c:     $(program_dir);$(screen_dir)
     .c.obj:
             $(compiler) $[* $(compile_options)

     main.obj : $(program_dir)main.c $(header_files)

     calc.obj : $(program_dir)calc.c $(header_files)

     input.obj : $(screen_dir)input.c $(header_files)

     output.obj : $(screen_dir)output.c $(header_files)

Suppose that there is a change in the "DEFS.H" file which causes all the source files to be recompiled.   The implicit rule ".c.obj" is invoked for every object file so the corresponding ".C" file must be found for each ".OBJ" file.  We will show where Make searches for the C/C++ source files.

     
     update    main.obj
       test    ..\c\program\main.c             (it does exist)
       execute wcc386 ..\c\program\main /mf /d1 /w3

     update    calc.obj
       test    ..\c\program\calc.c             (it does exist)
       execute wcc386 ..\c\program\calc /mf /d1 /w3

     update    input.obj
       test    ..\c\program\input.c       (it does not exist)
       test    ..\c\screen\input.c             (it does exist)
       execute wcc386 ..\c\screen\input /mf /d1 /w3

     update    output.obj
       test    ..\c\program\output.c      (it does not exist)
       test    ..\c\screen\output.c            (it does exist)
       execute wcc386 ..\c\screen\output /mf /d1 /w3

     etc.

Notice that Make checked the sub-directory "..\C\PROGRAM" for the files "INPUT.C" and "OUTPUT.C".   Make optionally may use a circular path specification search which may save on disk activity for large makefiles.  The circular path searching may be used in two different ways:
  1. use the command line option "o"
  2. use the .OPTIMIZE directive.

Make will retain (for each suffix) what sub-directory yielded the last successful search for a file.  The search for a file is resumed at this directory in the hope that wasted disk activity will be minimized.  If the file cannot be found in the sub-directory then Make will search the next sub-directory in the path specification (cycling to the first sub-directory in the path specification after an unsuccessful search in the last sub-directory).

Changing the previous example to include this feature, results in the following:

     
     #
     # programming example
     # (optimized path searching)
     #
     .OPTIMIZE

     h_dir        = ..\h\    # sub-directory with header files
                              # sub-directories with C/C++ source files
     program_dir  = ..\c\program\ # - MAIN.C, CALC.C
     screen_dir   = ..\c\screen\  # - INPUT.C, OUTPUT.C
     version      = debugging     # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     header_files = $(h_dir)defs.h $(h_dir)globals.h
     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c:     $(program_dir);$(screen_dir)
     .c.obj:
             $(compiler) $[* $(compile_options)

     main.obj : $(program_dir)main.c $(header_files)

     calc.obj : $(program_dir)calc.c $(header_files)

     input.obj : $(screen_dir)input.c $(header_files)

     output.obj : $(screen_dir)output.c $(header_files)

Suppose again that there is a change in the "DEFS.H" file which causes all the source files to be recompiled.   We will show where Make searches for the C/C++ source files using the optimized path specification searching.
     
     update    main.obj
       test    ..\c\program\main.c             (it does exist)
       execute wcc386 ..\c\program\main /mf /d1 /w3

     update    calc.obj
       test    ..\c\program\calc.c             (it does exist)
       execute wcc386 ..\c\program\calc /mf /d1 /w3

     update    input.obj
       test    ..\c\program\input.c       (it does not exist)
       test    ..\c\screen\input.c             (it does exist)
       execute wcc386 ..\c\screen\input /mf /d1 /w3

     update    output.obj
       test    ..\c\screen\output.c            (it does exist)
       execute wcc386 ..\c\screen\output /mf /d1 /w3

     etc.

Make did not check the sub-directory "..\C\PROGRAM" for the file "OUTPUT.C" because the last successful attempt to find a ".C" file occurred in the "..\C\SCREEN" sub-directory.  In this small example, the amount of disk activity saved by Make is not substantial but the savings become much more pronounced in larger makefiles.

Hint:  The simple heuristic method that Make uses for optimizing path specification searches namely, keeping track of the last successful sub-directory, is very effective in reducing the amount of disk activity during the processing of a makefile.  A pitfall to avoid is having two files with the same name in the path.  The version of the file that is used to update the target depends on the previous searches.  Care should be taken when using files that have the same name with path specifications.

Large makefiles for projects written in C/C++ may become difficult to maintain with all the header file dependencies.   Ignoring header file dependencies and using implicit rules may reduce the size of the makefile while keeping most of the functionality intact.  The previous example may be made smaller by using this idea.

     
     #
     # programming example
     # (no header dependencies)
     #
     .OPTIMIZE

     h_dir        = ..\h\    # sub-directory with header files
                              # sub-directories with C/C++ source files
     program_dir  = ..\c\program\ # - MAIN.C, CALC.C
     screen_dir   = ..\c\screen\  # - INPUT.C, OUTPUT.C
     version      = debugging     # debugging version

     msg_production = linking production version ...
     msg_debugging = linking debug version ...

     link_options_production =
     link_options_debugging = debug all
     link_options = $(link_options_$(version))

     compiler = wcc386
     compile_options_production = /mf /w3
     compile_options_debugging = /mf /d1 /w3
     compile_options = $(compile_options_$(version))

     object_files = main.obj input.obj calc.obj &
                    output.obj

     plot.exe : $(object_files)
             echo $(msg_$(version))
             wlink $(link_options) @$^*

     .c:     $(program_dir);$(screen_dir)
     .c.obj:
             $(compiler) $[* $(compile_options)

Implicit rules are very useful in this regard providing you are aware that you have to make up for the information that is missing from the makefile.  In the case of C/C++ programs, you must ensure that you force Make to compile any programs affected by changes in header files.  Forcing Make to compile programs may be done by touching source files (not recommended), deleting object files, or using the "a" option and targets on the command line.  Here is how the files "INPUT.OBJ" and "MAIN.OBJ" may be recompiled if a change in some header file affects both files.

Example:

     del input.obj
     del main.obj
     wmake

or using the "a" option

Example:

     wmake /a input.obj main.obj

The possibility of introducing bugs into programs is present when using this makefile technique because it does not protect the programmer completely from object modules becoming out-of-date.  The use of implicit rules without header file dependencies is a viable makefile technique but it is not without its pitfalls.

Double Colon Explicit Rules


Single colon ":" explicit rules are useful in many makefile applications.  However, the single colon rule has certain restrictions that make it difficult to express more complex dependency relationships.  The restrictions imposed on single colon ":" explicit rules are:
  1. only one command list is allowed for each target
  2. after the command list is executed, the target is considered up to date

The first restriction becomes evident when you want to update a target in different ways (i.e., when the target is out of date with respect to different dependents).  The double colon explicit rule removes this restriction.

     
     #
     # multiple command lists
     #
     target1 :: dependent1 dependent2
             command1

     target1 :: dependent3 dependent4
             command2

Notice that if "target1" is out of date with respect to either "dependent1" or "dependent2" then "command1" will be executed.  The double colon "::" explicit rule does not consider the target (in this case "target1") up to date after the command list is executed.  Make will continue to attempt to update "target1".  Afterwards "command2" will be executed if "target1" is out of date with respect to either "dependent3" or "dependent4".  It is possible that both "command1" and "command2" will be executed.  As a result of the target not being considered up to date, an implicit rule search will be conducted on "target1" also.  Make will process the double colon "::" explicit rules in the order that they are encountered in the makefile.  A useful application of the double colon "::" explicit rule involves maintaining and using prototype information generated by a compiler. 

     
     #
     # double colon "::" example
     #
     compiler = wcc386
     options = /w3

     # generate macros for the .OBJ and .DEF files
     template = module1.$(ext) module2.$(ext) module3.$(ext)
     ext = obj
     objs = $+ $(template) $-
     ext = def
     defs = $+ $(template) $-

     # add .DEF to the extensions list
     .EXTENSIONS:
     .EXTENSIONS: .exe .obj .def .c

     # implicit rules for the .OBJ and .DEF files
     .c.obj:
             $(compiler) $[* $(options)

     # generate the prototype file (only do a syntax check)
     .c.def:
             $(compiler) $[* $(options) /v/zs

     program.exe :: $(defs)
             erase *.err

     program.exe :: $(objs)
             wlink @$^*

The ".OBJ" files are updated to complete the update of the file "PROGRAM.EXE".  It is important to keep in mind that Make does not consider the file "PROGRAM.EXE" up to date until it has conducted a final implicit rule search.  The double colon "::" explicit rule is useful when describing complex update actions.

Preprocessing Directives


One of the primary objectives in using a make utility is to improve the development and maintenance of projects.  A programming project consisting of many makefiles in different sub-directories may become unwieldy to maintain.  The maintenance problem stems from the amount of duplicated information scattered throughout the project makefiles.  Make provides a method to reduce the amount of duplicated information present in makefiles.  Preprocessing directives provide the capability for different makefiles to make use of common information.

File Inclusion


A common solution to the "duplicated information" problem involves referencing text contained in one file from many different files.  Make supports file inclusion with the !include preprocessing directive.  The development of object libraries, using 16-bit Open Watcom C/C++, for the different 80x86 16-bit memory models provides an ideal example to illustrate the use of the !include preprocessing directive.
Sub-directory
Contents

\WINDOW
WINDOW.CMD, WINDOW.MIF

\WINDOW\H
PROTO.H, GLOBALS.H, BIOS_DEF.H

\WINDOW\C
WINDOW.C, KEYBOARD.C, MOUSE.C, BIOS.C

\WINDOW\SCSD
small model object files, MAKEFILE, WINDOW_S.LIB

\WINDOW\SCBD
compact model object files, MAKEFILE, WINDOW_C.LIB

\WINDOW\BCSD
medium model object files, MAKEFILE, WINDOW_M.LIB

\WINDOW\BCBD
large model object files, MAKEFILE, WINDOW_L.LIB

\WINDOW\BCHD
huge model object files, MAKEFILE, WINDOW_L.LIB

The WLIB command file "WINDOW.CMD" contains the list of library operations required to build the libraries.   The contents of "WINDOW.CMD" are:

     
     -+window
     -+bios
     -+keyboard
     -+mouse

The "-+" library manager command indicates to WLIB that the object file should be replaced in the library.

The file "WINDOW.MIF" contains the makefile declarations that are common to every memory model.  The ".MIF" extension will be used for all the Make Include Files discussed in this manual.  This extension is also in the default extension list so it is a recommended extension for Make include files.  The contents of the "WINDOW.MIF" file is as follows:

     
     #
     # example of a Make Include File
     #
     common = /d1 /w3          # common options
     objs = window.obj bios.obj keyboard.obj mouse.obj

     .c: ..\c
     .c.obj:
             wcc $[* $(common) $(local) /m$(model)

     window_$(model).lib : $(objs)
             wlib window_$(model) @..\window

The macros "model" and "local" are defined by the file "MAKEFILE" in each object directory.   An example of the file "MAKEFILE" in the medium memory model object directory is:

     
     #
     # !include example
     #
     model = m         # memory model required
     local =           # memory model specific options
     !include ..\window.mif

Notice that changes that affect all the memory models may be made in one file, namely "WINDOW.MIF".  Any changes that are specific to a memory model may be made to the "MAKEFILE" in the object directory.  To update the medium memory model library, the following commands may be executed: 

Example:

     C>cd \window\bcsd
     C>wmake

A DOS ".BAT" or OS/2 ".CMD" file may be used to update all the different memory models.  If the following DOS "MAKEALL.BAT" (OS/2 "MAKEALL.CMD") file is located somewhere in the "PATH", we may update all the libraries.

     
     cd \window\scsd
     wmake %1 %2 %3 %4 %5 %6 %7 %8 %9
     cd \window\scbd
     wmake %1 %2 %3 %4 %5 %6 %7 %8 %9
     cd \window\bcsd
     wmake %1 %2 %3 %4 %5 %6 %7 %8 %9
     cd \window\bcbd
     wmake %1 %2 %3 %4 %5 %6 %7 %8 %9
     cd \window\bchd
     wmake %1 %2 %3 %4 %5 %6 %7 %8 %9

The batch file parameters are useful if you want to specify options to Make.  For instance, a global recompile may be done by executing: 

Example:

     C>makeall /a

The !include preprocessing directive is a good way to partition common information so that it may be maintained easily.

Another use of the !include involves program generated makefile information.  For instance, if we have a program called "WMKMK" that will search through source files and generate a file called "WMKMK.MIF" that contains:

     
     #
     # program generated makefile information
     #
     C_to_OBJ = $(compiler) $[* $(compile_options)

     OBJECTS = WINDOW.OBJ BIOS.OBJ KEYBOARD.OBJ MOUSE.OBJ

     WINDOW.OBJ : ..\C\WINDOW.C ..\H\PROTO.H ..\H\GLOBALS.H
         $(C_to_OBJ)
     BIOS.OBJ : ..\C\BIOS.C ..\H\BIOS_DEF.H ..\H\GLOBALS.H
         $(C_to_OBJ)
     KEYBOARD.OBJ : ..\C\KEYBOARD.C ..\H\PROTO.H ..\H\GLOBALS.H
         $(C_to_OBJ)
     MOUSE.OBJ : ..\C\MOUSE.C ..\H\PROTO.H ..\H\GLOBALS.H
         $(C_to_OBJ)

In order to use this program generated makefile information, we use a "MAKEFILE" containing:

     
     #
     # makefile that makes use of generated makefile information
     #
     compile_options = /mf /d1 /w3

     first_target : window.lib .SYMBOLIC
             echo done

     !include wmkmk.mif

     window.lib : $(OBJECTS)
             wlib window $(OBJECTS)

     make : .SYMBOLIC
             wmkmk /r ..\c\*.c+..\c\*.cpp+..\h

Notice that there is a symbolic target "first_target" that is used as a "place holder".  The default behaviour for Make is to "make" the first target encountered in the makefile.  The symbolic target "first_target" ensures that we have control over what file will be updated first (in this case "WINDOW.LIB").   The use of the !include preprocessing directive simplifies the use of program generated makefile information because any changes are localized to the file "MAKEFILE".  As program development continues, the file "WMKMK.MIF" may be regenerated so that subsequent invocations of WMAKE benefit from the new makefile information.  The file "MAKEFILE" even contains the command to regenerate the file "WMKMK.MIF".  The symbolic target "make" has an associated command list that will regenerate the file "WMKMK.MIF".  The command list can be executed by typing the following command: 

Example:

     C>wmake make

The use of the !include preprocessing directive is a simple way to reduce maintenance of related makefiles.

Hint:  Macros are expanded on !include preprocessor control lines.  This allows many benefits like:

!include $(%env_var)

so that the files that Make will process can be controlled through many different avenues like internal macros, command line macros, and environment variables.

Another way to access files is through the suffix path feature of Make.  A definition like

.mif :  c:\mymifs;d:\some\more\mifs

will cause Make to search different paths for any make include files.

Conditional Processing


Open Watcom Make has conditional preprocessing directives available that allow different declarations to be processed.   The conditional preprocessing directives allow the makefile to
  1. check whether a macro is defined, and
  2. check whether a macro has a certain value.

The macros that can be checked include
  1. normal macros "$(<macro_identifier>)"
  2. environment macros "$(%<environment_var>)"

The conditional preprocessing directives allow a makefile to adapt to different external conditions based on the values of macros or environment variables.  We can define macros on the WMAKE command line as shown in the following example.

Example:

     C>wmake "macro=some text with spaces in it"

Alternatively, we can include a makefile that defines the macros if all the macros cannot fit on the command line.   This is shown in the following example:

Example:

     C>wmake /f macdef.mif /f makefile

Also, environment variables can be set before WMAKE is invoked.  This is shown in the following example:

Example:

     C>set macro=some text with spaces in it
     C>wmake

Now that we know how to convey information to Make through either macros or environment variables, we will look at how this information can be used to influence makefile processing.

Make has conditional preprocessing directives that are similar to the C preprocessor directives.  Make supports these preprocessor directives: 

     
     !ifeq
     !ifneq
     !ifeqi
     !ifneqi
     !ifdef
     !ifndef

along with

     
     !else
     !endif

Together these preprocessor directives allow selection of makefile declarations to be based on either the value or the existence of a macro.

Environment variables can be checked by using an environment variable name prefixed with a "%".  A common use of a conditional preprocessing directive involves setting environment variables. 

     
     #
     # setting an environment variable
     #
     !ifndef %lib

     .BEFORE
             set lib=c:\watcom\lib386;c:\watcom\lib386\dos
     !endif

If you are writing portable applications, you might want to have:

     
     #
     # checking a macro
     #
     !include version.mif

     !ifdef OS2
     machine = /2          # compile for 286
     !else
     machine = /0          # default: 8086
     !endif

The !ifdef ("if defined") and !ifndef ("if not defined") conditional preprocessing directives are useful for checking boolean conditions.  In other words, the !ifdef and !ifndef are useful for "yes-no" conditions.  There are instances where it would be useful to check a macro against a value.   In order to use the value checking preprocessor directives, we must know the exact value of a macro.  A macro definition is of the form:

     
     <macro_identifier> = <text> <comment>

Make will first strip any comment off the line.  The macro definition will then be the text following the equal "=" sign with leading and trailing blanks removed.  Initially this might not seem like a sensible way to define a macro but it does lend itself well to defining macros that are common in makefiles.  For instance, it allows definitions like:

     
     #
     # sample macro definitions
     #
     link_options    = debug line   # line number debugging
     compile_options = /d1 /s       # line numbers, no stack checking

These definitions are both readable and useful.  A makefile can handle differences between compilers with the !ifeq, !ifneq, !ifeqi and !ifneqi conditional preprocessing directives.  The first two perform case sensitive comparisons while the last two perform case insensitive comparisons.  One way of setting up adaptive makefiles is:

     
     #
     # options made simple
     #
     compiler        = wcc386

     stack_overflow  = No   # yes -> check for stack overflow
     line_info       = Yes  # yes -> generate line numbers

     !ifeq compiler wcc386
     !ifneqi stack_overflow   yes
     stack_option    =       /s
     !endif
     !ifeqi line_info         yes
     line_option     =       /d1
     !endif
     !endif

     !ifeq compiler tcc
     !ifeqi stack_overflow    yes
     stack_option    =       -N
     !endif
     !ifeqi line_info         yes
     line_option     =       -y
     !endif
     !endif

     #
     # make sure the macros are defined
     #
     !ifndef stack_option
     stack_option    =
     !endif
     !ifndef line_option
     line_option    =
     !endif

     example : .SYMBOLIC
             echo $(compiler) $(stack_option) $(line_option)

The conditional preprocessing directives can be very useful to hide differences, exploit similarities, and organize declarations for applications that use many different programs.

Another directive is the !define directive.  This directive is equivalent to the normal type of macro definition (i.e., macro = text) but will make C programmers feel more at home.  One important distinction is that the !define preprocessor directive may be used to reflect the logical structure of macro definitions in conditional processing.   For instance, the previous makefile could have been written in this style:

     
     !ifndef stack_option
     !  define stack_option
     !endif
     !ifndef line_option
     !  define line_option
     !endif

The "!" character must be in the first column but the directive keyword can be indented.  This freedom applies to all of the preprocessing directives.  The !else preprocessing directive benefits from this type of style because !else can also check conditions like:

     
     !else ifeq
     !else ifneq
     !else ifeqi
     !else ifneqi
     !else ifdef
     !else ifndef

so that logical structures like:

     
     !ifdef %version
     !  ifeq %version debugging
     !    define option debug all
     !  else ifeq %version beta
     !    define option debug line
     !  else ifeq %version production
     !    define option debug
     !  else
     !    error invalid value in VERSION
     !  endif
     !endif

can be used.  The above example checks the environment variable "VERSION" for three possible values and acts accordingly.

Another derivative from the C language preprocessor is the !error directive which has the form of

     
     !error <text>

in Make.  This directive will print out the text and terminate processing of the makefile.  It is very useful in preventing errors from macros that are not defined properly.  Here is an example of the !error preprocessing directive.

     
     !ifndef stack_option
     !  error stack_option is not defined
     !endif
     !ifndef line_option
     !  error line_option is not defined
     !endif

There is one more directive that can be used in a makefile.  The !undef preprocessing directive will clear a macro definition.  The !undef preprocessing directive has the form:
     
     !undef <macro_identifier>

The macro identifier can represent a normal macro or an environment variable.  A macro can be cleared after it is no longer needed.  Clearing a macro will reduce the memory requirements for a makefile.  If the macro identifier represents an environment variable (i.e., the identifier has a "%" prefix) then the environment variable will be deleted from the current environment.  The !undef preprocessing directive is useful for deleting environment variables and reducing the amount of internal memory required during makefile processing.
Open Watcom Make supports loading of Dynamic Link Library (DLL) versions of Open Watcom software through the use of the !loaddll preprocessing directive.  This support is available on Win32 and 32-bit OS/2 platforms.  Performance is greatly improved by avoiding a reload of the software for each file to be processed.  The syntax of the !loaddll preprocessing directive is:

     
     !loaddll $(exename) $(dllname)

where $(exename) is the command name used in the makefile and $(dllname) is the name of the DLL to be loaded and executed in its place.  For example, consider the following makefile which contains a list of commands and their corresponding DLL versions.

     
     # Default compilation macros for sample programs
     #
     # Compile switches that are enabled

     CFLAGS  = -d1
     CC      = wpp386 $(CFLAGS)

     LFLAGS  = DEBUG ALL
     LINK    = wlink  $(LFLAGS)

     !ifdef __LOADDLL__
     !  loaddll wcc      wccd
     !  loaddll wccaxp   wccdaxp
     !  loaddll wcc386   wccd386
     !  loaddll wpp      wppdi86
     !  loaddll wppaxp   wppdaxp
     !  loaddll wpp386   wppd386
     !  loaddll wlink    wlinkd
     !  loaddll wlib     wlibd
     !  loaddll wrc      wrcd
     !endif

     .c.obj:
             $(CC) $*.c

The __LOADDLL__ symbol is defined for versions of Open Watcom Make that support the !loaddll preprocessing directive.  The !ifdef __LOADDLL__ construct ensures that the makefile can be processed by an older version of Open Watcom Make.

Make will look up the wpp386 command in its DLL load table and find a match.  It will then attempt to load the corresponding DLL (i.e., wppd386.dll) and pass it the command line for processing.  The lookup is case insensitive but must match in all other respects.  For example, if a path is included with the command name then the same path must be specified in the !loaddll preprocessing directive.  This problem can be avoided through the use of macros as illustrated below.

     
     # Default compilation macros for sample programs
     #
     # Compile switches  that are enabled
     #
     cc286   = wpp
     cc286d  = wppdi86
     cc386   = wpp386
     cc386d  = wppd386
     linker  = wlink
     linkerd = wlinkd

     CFLAGS  = -d1
     CC      = $(cc386) $(CFLAGS)

     LFLAGS  = DEBUG ALL
     LINK    = wlink  $(LFLAGS)

     !ifdef __LOADDLL__
     !loaddll $(cc286)   $(cc286d)
     !loaddll $(cc386)   $(cc386d)
     !loaddll $(linker)  $(linkerd)
     !endif

     .c.obj:
             $(CC) $*.c

A path and/or extension may be specified with the DLL name if desired.

Command List Directives


Open Watcom Make supports special directives that provide command lists for different purposes.  If a command list cannot be found while updating a target then the directive .DEFAULT may be used to provide one.  A simple .DEFAULT command list which makes the target appear to be updated is: 

     
     .DEFAULT
             wtouch $^@

The Open Watcom Touch utility sets the time-stamp on the file to the current time.  The effect of the above rule will be to "update" the file without altering its contents. 

In some applications it is necessary to execute some commands before any other commands are executed and likewise it is useful to be able to execute some commands after all other commands are executed.  Make supports this capability by checking to see if the .BEFORE and .AFTER directives have been used.  If the .BEFORE directive has been used, the .BEFORE command list is executed before any commands are executed.  Similarly the .AFTER command list is executed after processing is finished.  It is important to note that if all the files are up to date and no commands must be executed, the .BEFORE and .AFTER command lists are never executed.  If some commands are executed to update targets and errors are detected (non-zero return status, macro expansion errors), the .AFTER command list is not executed (the .ERROR directive supplies a command list for error conditions and is discussed in this section).  These two directives may be used for maintenance as illustrated in the following example:  

     
     #
     # .BEFORE and .AFTER example
     #
     .BEFORE
             echo .BEFORE command list executed
     .AFTER
             echo .AFTER command list executed
     #
     # rest of makefile follows
     #
             .
             .
             .

If all the targets in the makefile are up to date then neither the .BEFORE nor the .AFTER command lists will be executed.  If any of the targets are not up to date then before any commands to update the target are executed, the .BEFORE command list will be executed.  The .AFTER command list will be executed only if there were no errors detected during the updating of the targets.  The .BEFORE, .DEFAULT, and .AFTER command list directives provide the capability to execute commands before, during, and after the makefile processing.  

Make also supports the .ERROR directive.  The .ERROR directive supplies a command list to be executed if an error occurs during the updating of a target.

     
     #
     # .ERROR example
     #
     .ERROR
             beep
     #
     # rest of makefile follows
     #
             .
             .
             .

The above makefile will audibly signal you that an error has occurred during the makefile processing.  If any errors occur during the .ERROR command list execution, makefile processing is terminated.

MAKEINIT File


As you become proficient at using Open Watcom Make, you will probably want to isolate common makefile declarations so that there is less duplication among different makefiles.  Make will search for a file called "MAKEINIT" (or "TOOLS.INI" when the "ms" option is set) and process it before any other makefiles.  The search for the "MAKEINIT" file will occur along the current "PATH".  If the file "MAKEINIT" is not found, processing continues without any errors.  By default, Make defines a set of data described at the "r" option.  The use of a "MAKEINIT" file will allow you to reuse common declarations and will result in simpler, more maintainable makefiles.

Command List Execution


Open Watcom Make is a program which must execute other programs and operating system shell commands.  There are three basic types of executable files in DOS and RDOS.
  1. .COM files
  2. .EXE files
  3. .BAT files

There are two basic types of executable files in Windows NT.
  1. .EXE files
  2. .BAT files

There are two basic types of executable files in OS/2.
  1. .EXE files
  2. .CMD files

The .COM and .EXE files may be loaded into memory and executed.  The .BAT files must be executed by the DOS command processor or shell, "COMMAND.COM".  The .CMD files must be executed by the OS/2 command processor or shell, "CMD.EXE" Make will search along the "PATH" for the command and depending on the file extension the file will be executed in the proper manner.

If Make detects any input or output redirection characters (these are ">", "<", and "|") in the command, it will be executed by the shell.

Under DOS, an asterisk prefix (*) will cause Make to examine the length of the command argument.  If it is too long (> 126 characters), it will take the command argument and stuff it into a temporary environment variable and then execute the command with "@env_var" as its argument.  Suppose the following sample makefile fragment contained a very long command line argument.

     
     #
     # Asterisk example
     #
         *foo myfile /a /b /c ... /x /y /z

Make will perform something logically similar to the following steps.

     
         set TEMPVAR001=myfile /a /b /c ... /x /y /z
         foo @TEMPVAR001

The command must, of course, support the "@env_var" syntax.  Typically, DOS commands do not support this syntax but many of the Open Watcom tools do.

The exclamation mark prefix (!) will force a command to be executed by the shell.  Also, the command will be executed by the shell if the command is an internal shell command from the following list:
break
check for Ctrl+Break

call
nest batch files

cd
change current directory

chdir
change current directory

cls
clear the screen

cmd
start NT or OS/2 command processor

command
start DOS command processor

ctty
DOS redirect input/output to COM port

d:
change drive where "d" represents a drive specifier

date
set system date

del
erase files

dir
display contents in a directory

echo
display commands as they are processed, intercepted by WMAKE

erase
erase files

for
repetitively process commands, intercepted by WMAKE

if
allow conditional processing of commands, intercepted by WMAKE

md
make directory

mkdir
make directory, intercepted by WMAKE

path
set search path

pause
suspend batch operations

prompt
change command prompt

ren
rename files

rename
rename files

rmdir
remove directory, intercepted by WMAKE

rd
remove directory

rm
erase files or directories, intercepted by WMAKE

set
set environment variables, intercepted by WMAKE

time
set system time

type
display contents of a file

ver
display the operating system version number

verify
set data verification

vol
display disk volume label

Below is description of all commands intercepted by Make.  Their syntax and functionality is derived from DOS version of these commands.  Some of them is not available on DOS OS, these commands syntax and functionality is derived from POSIX standard.

Any of these commands have not the same limitations as on appropriate OS and support features necessary for all supported OSes.

echo command


The operating system shell "echo" command is intercepted by Make.  It uses following syntax:

     
     echo [<value>]

The "echo" command may be used to output any string to standard output without length limitation.

set command


The operating system shell "set" command is intercepted by Make.  It uses following syntax:

     
     set <name> =[<value>]    (if no value then variable is deleted)

The "set" command may be used to set environment variables to values required during makefile processing.   The environment variable changes are only valid during makefile processing and do not affect the values that were in effect before Make was invoked.  The "set" command may be used to initialize environment variables necessary for the makefile commands to execute properly.  The setting of environment variables in makefiles reduces the number of "set" commands required in the system initialization file.  Here is an example with the Open Watcom C/C++ compiler. 

     
     #
     # set example
     #
     .BEFORE
             set include=c:\special\h;$(%include)
             set lib=c:\watcom\lib386;c:\watcom\lib386\dos
     #
     # rest of makefile follows
     #
             .
             .
             .

The first "set" command will set up the INCLUDE environment variable so that the Open Watcom C/C++ compiler may find header files.  Notice that the old value of the INCLUDE environment variable is used in setting the new value.

The second "set" command indicates to the Open Watcom Linker that libraries may be found in the indicated directories.

Environment variables may be used also as dynamic variables that may communicate information between different parts of the makefile.  An example of communication within a makefile is illustrated in the following example. 

     
     #
     # internal makefile communication
     #
     .BEFORE
             set message=message text 1
             echo *$(%message)*
             set message=
             echo *$(%message)*

     .example : another_target .SYMBOLIC
             echo *$(%message)*

     another_target : .SYMBOLIC
             set message=message text 2

The output of the previous makefile would be:

     
     (command output only)
     *message text 1*
     **
     *message text 2*

Make handles the "set" command so that it appears to work in an intuitive manner similar to the operating system shell's "set" command.  The "set" command also may be used to allow commands to relay information to commands that are executed afterwards.

for command


The operating system shell "for" command is intercepted by Make.  It uses following syntax:

     
     for %[%]<var> in (<set>) do <command>

DOS has a fixed limit for the size of a command thus making it unusable for large makefile applications.  One such application that can be done easily with Make is the construction of a WLINK command file from a makefile.  The idea behind the next example is to have one file that contains the list of object files.  Anytime this file is changed, say, after a new module has been added, a new linker command file will be generated which in turn, will cause the linker to relink the executable.  First we need the makefile to define the list of object files, this file is "OBJDEF.MIF" and it declares a macro "objs" which has as its value the list of object files in the application.  The content of the "OBJDEF.MIF" file is:

     
     #
     # list of object files
     #
     objs = &
          window.obj &
          bios.obj &
          keyboard.obj &
          mouse.obj

The main makefile ("MAKEFILE") is:

     
     #
     # for command example
     #
     !include objdef.mif

     plot.exe : $(objs) plot.lnk
             wlink @plot

     plot.lnk : objdef.mif
             echo NAME $^& >$^@
             echo DEBUG all >>$^@
             for %i in ($(objs)) do echo FILE %i >>$^@

This makefile would produce a file "PLOT.LNK" automatically whenever the list of object files is changed (anytime "OBJDEF.MIF" is changed).  For the above example, the file "PLOT.LNK" would contain:

     
     NAME plot
     DEBUG all
     FILE window.obj
     FILE bios.obj
     FILE keyboard.obj
     FILE mouse.obj

if command


The operating system shell "if" command is intercepted by Make.  It uses following syntax:

     
                 { errorlevel <number> }
        if [not] { <str1> == <str2>    } <command>
                 { exist <file>         }

It handles file names consistently with other Make commands.

rm command


The commands "rm" is intercepted by Make.  It uses following syntax:

     
     rm [-frv] <files/directories>

The "rm" command may be used to delete files or directories.  Make "rm" command is simplified implementation of the POSIX rm command.  It handles file/directory names consistently with other Make commands.  Following options are support.
-f
force deletion of read-only files, no diagnostics messages about missing items

-r
deletion of directories

-v
verbose operation

mkdir command


The commands "mkdir" is intercepted by Make.  It uses following syntax:

     
     mkdir [-p] <directory>

The "mkdir" command may be used to create a directory.  Make "mkdir" command is simplified implementation of the POSIX "mkdir" command.  It handles directory names consistently with other Make commands.   Following options are support.
-p
force creation of all parent directories

rmdir command


The commands "rmdir" is intercepted by Make.  It uses following syntax:

     
     rmdir <directory>

The "rmdir" command may be used to delete a directory.  Make "rmdir" command is is simplified implementation of the POSIX "rmdir" command.  It handles directory names consistently with other Make commands.

Make internal commands


Make supports nine internal commands:
  1. %abort
  2. %append
  3. %copy
  4. %create
  5. %erase
  6. %make
  7. %null
  8. %quit
  9. %ren
  10. %stop
  11. %write

The %abort and %quit internal commands terminate execution of Make and return to the operating system shell:  %abort sets a non-zero exit code; %quit sets a zero exit code.

     
     #
     # %abort and %quit example
     #
     done_enough :
             %quit

     suicide :
             %abort

The %append, %create, %erase, and %write internal commands allow WMAKE to generate files under makefile control.  This is useful for files that have contents that depend on makefile contents.  Through the use of macros and the "for" command, Make becomes a very powerful tool in maintaining lists of files for other programs.

The %append internal command appends a text line to the end of a file (which is created if absent) while the %write internal command creates or truncates a file and writes one line of text into it.  Both commands have the same form, namely:

     
     %append <file> <text>
     %write <file> <text>

where <file> is a file specification and <text> is arbitrary text.

The %copy internal command will copy a file.  The command has the form:

     
     %copy <from file> <to file>

where <from file> and <to file> are a file specification.

The %ren internal command will rename a file.  The command has the form:

     
     %ren <from file> <to file>

where <from file> and <to file> are a file specification.

The %create internal command will create or truncate a file so that the file does not contain any text while the %erase internal command will delete a file.  Both commands have the same form, namely:

     
     %create <file>
     %erase <file>

where <file> is a file specification.

Full macro processing is performed on these internal commands so the full power of WMAKE can be used.  The following example illustrates a common use of these internal commands. 

     
     #
     # %append, %create, %erase, and %write example
     #
     !include objdef.mif

     plot.exe : $(objs) plot.lnk
             wlink @plot

     plot.lnk : objdef.mif
             %create $^@
             %append $^@ NAME $^&
             # Next line equivalent to previous two lines.
             %create $^@ NAME $^&
             %append $^@ DEBUG all
             for %i in ($(objs)) do %append $^@ FILE %i

     clean : .SYMBOLIC
             %erase plot.lnk

The above code demonstrates a valuable technique that can generate directive files for WLINK, WLIB, and other utilities.

The %make internal command permits the updating of a specific target and has the form:

     
     %make <target>

where <target> is a target in the makefile. 

     
     #
     # %make example
     #
     !include objdef.mif

     plot.exe : $(objs)
             %make plot.lnk
             wlink @plot

     plot.lnk : objdef.mif
             %create $^@
             %append $^@ NAME $^&
             %append $^@ DEBUG all
             for %i in ($(objs)) do %append $^@ FILE %i

There seem to be other ways of doing the same thing.  Among them is putting plot.lnk into the list of dependencies:

     
     #
     # %make counter-example
     #
     !include objdef.mif

     plot.exe : $(objs) plot.lnk
             wlink @plot

     plot.lnk : objdef.mif
             %create $^@
             %append $^@ NAME $^&
             %append $^@ DEBUG all
             for %i in ($(objs)) do %append $^@ FILE %i

and using a make variable:

     
     #
     # %make counter-example
     #
     !include objdef.mif

     plot.exe : $(objs)
             wlink NAME $^& DEBUG all FILE { $(objs) }

The %null internal command does absolutely nothing.  It is useful because Make demands that a command list be present whenever a target is updated. 

     
     #
     # %null example
     #
     all : application1 application2 .SYMBOLIC
             %null

     application1 : appl1.exe .SYMBOLIC
             %null

     application2 : appl2.exe .SYMBOLIC
             %null

     appl1.exe : (dependents ...)
             (commands)

     appl2.exe : (dependents ...)
             (commands)

Through the use of the %null internal command, multiple application makefiles may be produced that are quite readable and maintainable.

The %stop internal command will temporarily suspend makefile processing and print out a message asking whether Makefile processing should continue.  Make will wait for either the "y" key (indicating that the Makefile processing should continue) or the "n" key.  If the "n" key is pressed, makefile processing will stop.  The %stop internal command is very useful for debugging makefiles but it may be used also to develop interactive makefiles.

     
     #
     # %stop example
     #
     all : appl1.exe .SYMBOLIC
             %null

     appl1.exe : (dependents ...)
             @echo Are you feeling lucky? Punk!
             @%stop
             (commands)

Compatibility Between Open Watcom Make and UNIX Make


Open Watcom Make was originally based on the UNIX Make utility.  The PC's operating environment presents a base of users which may or may not be familiar with the UNIX operating system.  Make is designed to be a PC product with some UNIX compatibility.  The line continuation in UNIX Make is a backslash ("\") at the end of the line.  The backslash ("\") is used by the operating system for directory specifications and as such will be confused with line continuation.  For example, you could type:

     
     cd \

along with other commands ...  and get unexpected results.  However, if your makefile does not contain path separator characters ("\") and you wish to use "\" as a line continuation indicator then you can use the Make "u" (UNIX compatibility mode) option.

Also, in the UNIX operating system there is no concept of file extensions, only the concept of a file suffix.  Make will accept the UNIX Make directive .SUFFIXES for compatibility with UNIX makefiles.  The UNIX compatible special macros supported are:
Macro
Expansion

$@
full name of the target

$*
target with the extension removed

$<
list of all dependents

$?
list of dependents that are younger than the target

The extra checking of makefiles done by Make will require modifications to UNIX makefiles.  The UNIX Make utility does not check for the existence of targets after the associated command list is executed so the "c" or the .NOCHECK directive should be used to disable this checking.  The lack of a command list to update a target is ignored by the UNIX Make utility but Open Watcom Make requires the special internal command %null to specify a null command list.  In summary, Make supports many of the features of the UNIX Make utility but is not 100% compatible.

Open Watcom Make Diagnostic Messages


This section lists the various warning and error messages that may be issued by the Open Watcom Make.  In the messages below, %?  character sequences indicate places in the message that are replaced with some other string.
1
Out of memory

2
Make execution terminated

3
Option %c%c invalid

4
%c%c must be followed by a filename

5
No targets specified

6
Ignoring first target in MAKEINIT

7
Expecting a %M

8
Invalid macro name %E

9
Ignoring out of place %M

10
Macros nested too deep

11
Unknown internal command

12
Program name is too long

13
No control characters allowed in options

14
Cannot execute %E:  %Z

15
Syntax error in %s command

16
Nested %s loops not allowed

17
Token too long, maximum size is %d chars

18
Unrecognized or out of place character '%C'

19
Target %E already declared %M

20
Command list does not belong to any target

21
Extension(s) %E not defined

22
No existing file matches %E

23
Extensions reversed in implicit rule

24
More than one command list found for %E

25
Extension %E declared more than once

26
Unknown preprocessor directive:  %s

27
Macro %E is undefined

28
!If statements nested too deep

29
!%s has no matching !if

30
Skipping !%1 block after !%2

31
%1 not allowed after !%2

32
Opening file %E:  %Z

34
!%s pending at end of file

35
Trying to !%s an undefined macro

36
Illegal attempt to update special target %E

37
Target %E is defined recursively

38
%E does not exist and cannot be made from existing files

39
Target %E not mentioned in any makefile

40
Could not touch %E

41
No %s commands for making %E

42
Last command making (%L) returned a bad status

43
Deleting %E:  %Z

44
%s command returned a bad status

45
Maximum string length exceeded

46
Illegal character value %xH in file

47
Assuming target(s) are .%s

48
Maximum %%make depth exceeded

49
Opening (%s) for write:  %Z

50
Unable to write:  %Z

51
CD'ing to %E:  %Z

52
Changing to drive %C:

53
DOS memory inconsistency detected!  System may halt ...

53
OS corruption detected

54
While reading (%s):  %Z

59
!IF Parse Error

60
TMP Path/File Too Long

61
Unexpected End of File

62
Only NO(KEEP) allowed here

63
Non-matching "

64
Invalid String Macro Substitution

65
File Name Length Exceeded

66
Redefinition of .DEFAULT Command List

67
Non-matching { In Implicit Rule

68
Invalid Implicit Rule Definition

69
Path Too Long

70
Cannot Load/Unload DLL %E

71
Initialization of DLL %E returned a bad status

72
DLL %E returned a bad status

73
Illegal Character %C in macro name

74
in closing file %E

75
in opening file %E

76
in writing file %E

77
User Break Encountered

78
Error in Memory Tracking Encountered

79
Makefile may be Microsoft; try /ms switch

80
Expecting double quote character to end open string

The Touch Utility


This chapter describes the Open Watcom Touch utility.  Open Watcom Touch will set the time-stamp (i.e., the modification date and time) of one or more files.  The new modification date and time may be the current date and time, the modification date and time of another file, or a date and time specified on the command line.  This utility is normally used in conjunction with the Open Watcom Make utility.  The rationale for bringing a file up-to-date without altering its contents is best understood by reading the chapter which describes the Make utility.

The Open Watcom Touch command line syntax is: 

     
     WTOUCH [options] file_spec [file_spec...]

The square brackets [ ] denote items which are optional.
options
is a list of valid options, each preceded by a slash ("/") or a dash ("-").  Options may be specified in any order.

file_spec
is the file specification for the file to be touched.  Any number of file specifications may be listed.  The wild card characters "*" and "?" may be used.

The following is a description of the options available.
c
do not create an empty file if the specified file does not exist

d <date>
specify the date for the file time-stamp in "mm-dd-yy" format

f <file>
use the time-stamp from the specified file

i
increment time-stamp before touching the file

q
suppress informational messages

r
touch file even if it is marked read-only

t <time>
specify the time for the file time-stamp in "hh:mm:ss" format

u
use USA date/time format regardless of country

?
display help screen

WTOUCH Operation


WTOUCH is used to set the time-stamp (i.e., the modification date and time) of a file.  The contents of the file are not affected by this operation.  If the specified file does not exist, it will be created as an empty file.  This behaviour may be altered with the "c" option so that if the file is not present, a new empty file will not be created.

Example:

     (will not create myfile.dat)
     C>wtouch /c myfile.dat

If a wild card file specification is used and no files match the pattern, no files will have their time-stamps altered.   The date and time that all the specified files are set to is determined as follows:
  1. The current date and time is used as a default value.
  2. A time-stamp from an "age file" may replace the current date and time.  The "f" option is used to specify the file that will supply the time-stamp.

    Example:

         (use the date and time from file "last.tim")
         C>wtouch /f last.tim file*.dat
  3. The date and/or time may be specified from the command line to override a part of the time-stamp that will be used.  The "d" and "t" options are used to override the date and time respectively.

    Example:

         (use current date but use different time)
         C>wtouch /t 2:00p file*.dat
         (completely specify date and time)
         C>wtouch /d 10-31-90 /t 8:00:00 file*.dat
         (use date from file "last.tim" but set time)
         C>wtouch /f last.tim /t 12:00 file*.dat

    The format of the date and time on the command line depends on the country information provided by the host operating system.  Open Watcom Touch should accept dates and times in a similar format to any operating system utilities (i.e., the DATE and TIME utilities provided by DOS).  The "a" and "p" suffix is an extension to the time syntax for specifying whether the time is A.M.  or P.M., but this is only available if the operating system is not configured for military or 24-hour time.

The IDE2MAKE Utility


This chapter describes the IDE2MAKE utility.  IDE2MAKE loads an IDE project file and, using the associated .tgt files, generates make files that can be invoked with WMAKE.  If the .wpj file does not exist, a default project is used.  If any tgtfile(s) are specified, they are used as the targets in creating the make files.

The IDE2MAKE command line syntax is: 

     
     ide2make [options] [tgtfile]

The square brackets [ ] denote items which are optional.  At least one item must be specified, otherwise the program usage is shown.
options
is a list of valid options, each preceded by a slash ("/") or a dash ("-").  Options may be specified in any order.

tgtfile
is the file specification for the targetfile to be used.  Any number of file specifications may be listed.

The following is a description of the options available.
p <wpjfile>
loads wpjfile.wpj (project.wpj by default)

c <cfgfile>
loads cfgfile instead of ide.cfg

i
directory to search configuration files

d
generate makefiles using development switch set

l
generate makefiles with long lines (no length limit)

r
generate makefiles using release switch set

h <number>
generate makefiles for selected host OS (default is current host)
0 - Windows 3.x
1 - OS/2 PM
2 - Windows NT
3 - Win-OS/2
4 - Windows 95
5 - Japanese Windows 3.x on an IBM
6 - Japanese Windows 3.x on a Nec98
7 - Dec Alpha (Windows NT)
8 - DOS
9 - Linux

IDE2MAKE Operation


IDE2MAKE is used to create makefiles from IDE project and targetfiles.  If no targetfile is specified, makefiles for all targets are generated.