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MAKEDEPEND(1)           FreeBSD General Commands Manual          MAKEDEPEND(1)

       makedepend - create dependencies in makefiles

       makedepend [ -Dname=def ] [ -Dname ] [ -Iincludedir ] [ -Yincludedir ]
       [ -a ] [ -fmakefile ] [ -include file ] [ -oobjsuffix ] [ -pobjprefix ]
       [ -sstring ] [ -wwidth ] [ -v ] [ -m ] [ -- otheroptions -- ]
       sourcefile ...

       The makedepend program reads each sourcefile in sequence and parses it
       like a C-preprocessor, processing all #include, #define, #undef,
       #ifdef, #ifndef, #endif, #if, #elif and #else directives so that it can
       correctly tell which #include, directives would be used in a
       compilation.  Any #include, directives can reference files having other
       #include directives, and parsing will occur in these files as well.

       Every file that a sourcefile includes, directly or indirectly, is what
       makedepend calls a dependency. These dependencies are then written to a
       makefile in such a way that make(1) will know which object files must
       be recompiled when a dependency has changed.

       By default, makedepend places its output in the file named makefile if
       it exists, otherwise Makefile.  An alternate makefile may be specified
       with the -f option.  It first searches the makefile for the line

           # DO NOT DELETE THIS LINE -- make depend depends on it.

       or one provided with the -s option, as a delimiter for the dependency
       output.  If it finds it, it will delete everything following this to
       the end of the makefile and put the output after this line.  If it
       doesn't find it, the program will append the string to the end of the
       makefile and place the output following that.  For each sourcefile
       appearing on the command line, makedepend puts lines in the makefile of
       the form

            sourcefile.o: dfile ...

       Where sourcefile.o is the name from the command line with its suffix
       replaced with ``.o'', and dfile is a dependency discovered in a
       #include directive while parsing sourcefile or one of the files it

       Normally, makedepend will be used in a makefile target so that typing
       ``make depend'' will bring the dependencies up to date for the
       makefile.  For example,
           SRCS = file1.c file2.c ...
           CFLAGS = -O -DHACK -I../foobar -xyz
                   makedepend -- $(CFLAGS) -- $(SRCS)

       The program will ignore any option that it does not understand so that
       you may use the same arguments that you would for cc(1).

       -Dname=def or -Dname
            Define.  This places a definition for name in makedepend's symbol
            table.  Without =def the symbol becomes defined as ``1''.

            Include directory.  This option tells makedepend to prepend
            includedir to its list of directories to search when it encounters
            a #include directive.  By default, makedepend only searches the
            standard include directories (usually /usr/include and possibly a
            compiler-dependent directory).

            Replace all of the standard include directories with the single
            specified include directory; you can omit the includedir to simply
            prevent searching the standard include directories.

       -a   Append the dependencies to the end of the file instead of
            replacing them.

            Filename.  This allows you to specify an alternate makefile in
            which makedepend can place its output.  Specifying ``-'' as the
            file name (i.e., -f-) sends the output to standard output instead
            of modifying an existing file.

       -include file
            Process file as input, and include all the resulting output before
            processing the regular input file. This has the same affect as if
            the specified file is an include statement that appears before the
            very first line of the regular input file.

            Object file suffix.  Some systems may have object files whose
            suffix is something other than ``.o''.  This option allows you to
            specify another suffix, such as ``.b'' with -o.b or ``:obj'' with
            -o:obj and so forth.

            Object file prefix.  The prefix is prepended to the name of the
            object file. This is usually used to designate a different
            directory for the object file.  The default is the empty string.

            Starting string delimiter.  This option permits you to specify a
            different string for makedepend to look for in the makefile.

            Line width.  Normally, makedepend will ensure that every output
            line that it writes will be no wider than 78 characters for the
            sake of readability.  This option enables you to change this

       -v   Verbose operation.  This option causes makedepend to emit the list
            of files included by each input file.

       -m   Warn about multiple inclusion.  This option causes makedepend to
            produce a warning if any input file includes another file more
            than once.  In previous versions of makedepend this was the
            default behavior; the default has been changed to better match the
            behavior of the C compiler, which does not consider multiple
            inclusion to be an error.  This option is provided for backward
            compatibility, and to aid in debugging problems related to
            multiple inclusion.

       -- options --
            If makedepend encounters a double hyphen (--) in the argument
            list, then any unrecognized argument following it will be silently
            ignored; a second double hyphen terminates this special treatment.
            In this way, makedepend can be made to safely ignore esoteric
            compiler arguments that might normally be found in a CFLAGS make
            macro (see the EXAMPLE section above).  All options that
            makedepend recognizes and appear between the pair of double
            hyphens are processed normally.

       The approach used in this program enables it to run an order of
       magnitude faster than any other ``dependency generator'' I have ever
       seen.  Central to this performance are two assumptions: that all files
       compiled by a single makefile will be compiled with roughly the same -I
       and -D options; and that most files in a single directory will include
       largely the same files.

       Given these assumptions, makedepend expects to be called once for each
       makefile, with all source files that are maintained by the makefile
       appearing on the command line.  It parses each source and include file
       exactly once, maintaining an internal symbol table for each.  Thus, the
       first file on the command line will take an amount of time proportional
       to the amount of time that a normal C preprocessor takes.  But on
       subsequent files, if it encounters an include file that it has already
       parsed, it does not parse it again.

       For example, imagine you are compiling two files, file1.c and file2.c,
       they each include the header file header.h, and the file header.h in
       turn includes the files def1.h and def2.h.  When you run the command

           makedepend file1.c file2.c

       makedepend will parse file1.c and consequently, header.h and then
       def1.h and def2.h.  It then decides that the dependencies for this file

           file1.o: header.h def1.h def2.h

       But when the program parses file2.c and discovers that it, too,
       includes header.h, it does not parse the file, but simply adds
       header.h, def1.h and def2.h to the list of dependencies for file2.o.

       cc(1), make(1)

       makedepend parses, but does not currently evaluate, the SVR4
       #predicate(token-list) preprocessor expression; such expressions are
       simply assumed to be true.  This may cause the wrong #include
       directives to be evaluated.

       Imagine you are parsing two files, say file1.c and file2.c, each
       includes the file def.h.  The list of files that def.h includes might
       truly be different when def.h is included by file1.c than when it is
       included by file2.c.  But once makedepend arrives at a list of
       dependencies for a file, it is cast in concrete.

       Todd Brunhoff, Tektronix, Inc. and MIT Project Athena

4th Berkeley Distribution        Version 4.7.0                   MAKEDEPEND(1)


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