MAKE: Orchestrate build
Documentation for make.exe for Win32Command line syntax
make {target} {macro=text} {switch}
| Argument | Description |
|---|---|
| target | What targets to make |
| macro=text | Define macro to be text |
| -d | Output debugging info |
| -ffile | Use file instead of makefile |
| -f file | Use file instead of makefile |
| -f- | Read makefile from stdin |
| -h | Print help message |
| -i | Ignore errors from executing make rules |
| -l | Show macro expansions in makefile |
| -man | Open browser on this page |
| -n | Make rules are not executed, just written to stdout |
| -q | Return with errorlevel 1 if rules would be executed |
| -s | Do not echo make rules |
| -t | Just touch files |
Environment Variables
make looks for the environment variable MAKEFLAGS upon startup. The string for MAKEFLAGS, if any, is parsed as if it was typed on the command line for the actual command line is parsed. For example:
SET MAKEFLAGS=CFLAGS=-D make target
is equivalent to:
make CFLAGS=-D target
The Makefile
A makefile is a text file containing a sequence of:
- Comment lines
- Blank lines
- Macro definition lines
- Explicit definition lines
- Implicit definition lines
- Rule lines
If the last character on a line is a \, then the line is concatenated with the next line in the file. The \ and all immediately following spaces and tabs are removed and replaced with a single space.
Comment lines
Comment lines are lines in which the first non-blank character is a #. Comment lines are ignored. Comment lines are removed before \ line splicing is done.Blank lines
Blank lines contain zero or more tabs or spaces. Blank lines are ignored.Macro definition lines
Macros are defined with lines of the form:MACRO = textSpaces and tabs around the = are stripped. They are used:
$(MACRO)
Single character macro names do not need () when expanded. Definitions for macros are searched for in the following order:
- Definitions from the command line.
- Definitions in the makefile.
- Definitions from the environment.
- The macro is expanded to nothing.
Explicit Definition lines
target [target ...] : [dependency ...] [; rule] [# ... ]
Implicit Definition lines
.targ_ext.dep_ext : [; rule] [# ... ]
Rule lines
tab [rule flag] rule [# ...]
Predefined macros
| Macro | Description |
|---|---|
| $? | List of dependencies that are newer than target |
| $** | Full list of dependencies |
| $* | Name of current target without extension |
| $< | From name of current target, if made using a implicit rule |
| $@ | Full target name |
| $$ | Expand to $ |
Rule flags
Rules can be preceeded by one of the following characters:
| Flag | Description |
|---|---|
| + | Force use of COMMAND.COM or CMD.EXE to execute the rule. This is useful for .BAT files |
| - | Ignore exit status from this rule |
| @ | Do not echo this rule when it's executed |
| * | Use _CMDLINE environment variable to pass long command lines |
| ~ | Use _CMDLINE environment variable to pass command line |
Win32 internal commands
The following commands are internal to Win32, that is, when make executes one it does so by executing CMD.EXE and passing the line to be executed to it. The internal commands are:
break,cd,chdir,cls,copy,ctty, date,del,dir,echo,erase,exit, if,md,mkdir,pause, rd,rem,rmdir,ren,rename, time,type,ver,verify,vol
Long command lines
Windows and DOS have limits on the length of a command line. Under DOS, this limit is 127. Under Win32, it varies from version to version and can depend on end user configuration. make assumes a command line limit of 996. If this limit is exceeded, and the rule is known to or flagged as accepting long command lines via the environment, the long command line is passed via the environment variable _CMDLINE. The actual command line the rule sees is @_CMDLINE. If writing programs to make use of this, use the response_expand() function in the program. To flag a rule as accepting this form, use the * rule flag. If running under a version of Windows that cannot handle 996 character command lines, use the ~ rule flag to tell make to pass the command line via _CMDLINE.
Special targets
| Target | Description |
|---|---|
| .SILENT | Same as if -s was specified on command line. Do not put a : after this |
| .IGNORE | Same as if -i was specified on command line. Do not put a : after this. |
| .DEFAULT | Rules following this target are executed for targets that have no rules specified for them. Any dependencies listed for the .DEFAULT target are ignored |
Default makefile
The default makefile (if the -f flag is not given) is "makefile".
Logging
For long and verbose makes, the output of make along with all messages can be redirected to a log file for later perusal.
make >log
Note that only stdout output of programs run by make are redirected. dmc.exe, etc. all redirect fine. masm 4.0 and earlier versions won't.
Error messages
- undefined switch 'xxxx'
- bad macro definition 'xxxx'
- can't read makefile 'xxxx'
- target must appear before commands
- bad macro definition 'xxxx'
- Can't specify rules before any targets.
- unrecognized target 'xxxx'
- Target was not one of .SILENT or .IGNORE.
- command line too long
- Rules to be executed by CMD.EXE cannot exceed 124 bytes
in length.
- expanded line is too long
- Argument to a command exceeds 127 bytes in length.
- ')' expected
- expecting target : dependencies
- Could not decipher target line.
- ambiguous implicit rule
- Two implicit rules were found for the same from and to
extensions.
- bad syntax for implicit rule
- Implicit rule syntax is of the form:
.from.to :
No dependencies are allowed for a implicit rule. - undefined macro 'xxxx'
- don't know how to make 'xxxx'
- The file xxxx does not exist and no rules were specified
for making it.
- 'xxxx' not found
- Could not find the command xxxx along the search path.
- out of memory
Other
When a rule is executed and it returns a non-zero exit status, the message:
--- errorlevel exitstatus
is printed and make terminates (unless make was instructed to ignore the exit status).
A # indicates a comment. The rest of the line is ignored.