In addition to the TOOLS.INI file, NMAKE32 supports the use of an optional file named BUILTINS.MAK. NMAKE32 will process either the TOOLS.INI or the BUILTINS.MAK file. If a TOOLS.INI file is not found, or the nmake section does not exist, NMAKE32 automatically searches for the BUILTINS.MAK file in the current directory or the file as specified by the -b flag. When an initialization file is processed, it is included as part of the makefile currently being executed. This feature allows the user to supplement the set of predefined macros that NMAKE32 supports and to maintain an additional set of inference rules.

Like the TOOLS.INI file, the BUILTINS.MAK file can be used to customize default options for NMAKE32. For example, if an inference rule is needed for several description files, instead of modifying all the description files, the rule can be added to the BUILTINS.MAK file. Unlike the TOOLS.INI file, an "[nmake]" section is not expected. All lines from the file are expected to be valid description file statements.

Example:

The lines in the BUILTINS.MAK file below do the following:

• Define the CFLAGS macro as a null string

• Redefine the predefined inference rule to build .obj files from .c source files using the CFLAGS macro

CFLAGS=.c.obj:
    $(CC) -c $(CFLAGS) $*.