DragonFly On-Line Manual Pages

MKDEP(1)               DragonFly General Commands Manual              MKDEP(1)

NAME
     mkdep - construct Makefile dependency list

SYNOPSIS
     mkdep [-ap] [-f file] [-S srcdir] [flags] file ...

DESCRIPTION
     The mkdep utility takes a set of flags for the C compiler and a list of C
     source files as arguments and constructs a set of include file
     dependencies which are written into the file .depend.  An example of its
     use in a Makefile might be:

           CFLAGS= -O -I../include
           SRCS= file1.c file2.c

           depend:
                   mkdep ${CFLAGS} ${SRCS}

     where the macro SRCS is the list of C source files and the macro CFLAGS
     is the list of flags for the C compiler.

     The user has the ability to change the preprocessor and preprocessor
     options used.  For instance, to use gcc as the preprocessor and to ignore
     system headers, one would use

           depend:
                   env MKDEP_CPP="gcc -E" MKDEP_CPP_OPTS=-MM mkdep \
                           ${CFLAGS} ${SRCS}

     The options are as follows:

     -a      Append to the output file, so that multiple mkdep's may be run
             from a single Makefile.

     -f file
             Write the include file dependencies to file, instead of the
             default .depend.

     -p      Cause mkdep to produce dependencies of the form:

                   program: program.c

             so that subsequent makes will produce program directly from its C
             module rather than using an intermediate .o module.  This is
             useful for programs whose source is contained in a single module.

     -S srcdir
             Treat srcdir as the root of the source tree, and prefix each
             dependency target with the path of its source file relative to
             srcdir, excluding the file name itself.  A source file located
             directly in srcdir, with no intervening subdirectory, is left
             unqualified.  The match is textual (i.e., no path normalization):
             srcdir must appear literally at the start of each source pathname
             given on the command line.

             Without specifying -S, sources that share a file name in
             different subdirectories produce identical targets, which can
             cause build failures or broken output.  This option avoids this
             by qualifying each target with its subdirectory.

             For example, the command

                   mkdep -S /src /src/abc.c /src/dir1/abc.c /src/dir2/abc.c

             generates:

                   abc.o: /src/abc.c
                   dir1/abc.o: /src/dir1/abc.c
                   dir2/abc.o: /src/dir2/abc.c

ENVIRONMENT
     CC              Specifies the C compiler to use.  The specified compiler
                     is expected to have options consistent with the GNU C
                     compiler.

     MKDEP_CPP       Specifies the preprocessor to use.  The default is "${CC}
                     -E".

     MKDEP_CPP_OPTS  Specifies the non-CFLAGS options for the preprocessor.
                     The default is "-M".

FILES
     .depend  File containing list of dependencies.

SEE ALSO
     cc(1), cpp(1), make(1)

HISTORY
     The mkdep command appeared in 4.3BSD-Tahoe.

DragonFly 6.5-DEVELOPMENT       August 24, 2026      DragonFly 6.5-DEVELOPMENT