403 

   404 Extracting version from VCS.

   405 ============================

   406 

   407 Including version in sources.

   408 =============================

   409 

   410 Don't use any ``$REVISION`` like keywords (usual practice in CVS, SVN)!

   411 

   412 Use sed, awk, M4 or any other preprocessor for non-compiled or non-preprocessed

   413 files (like .lisp, .py, .java files)::

   414 

   415   $ cat my-version.el.in

   416   (defvar my-major-version @VMAJOR@

   417     "Major version.")

   418   (defvar my-major-version @VMAJOR@

   419     "Major version.")

   420   (provide 'my-version)

   421 

   422   $ cat Makefile

   423   %: %.in

   424       sed -e 's|@VMAJOR@|$(VMAJOR)|' -e 's|@VMINOR@|$(VMINOR)|' <$< >$@

   425 

   426 Pass version component to preprocessed file (like .c, .cxx files) through

   427 preprocessor::

   428 

   429   $ cat my-version.c

   430   int get_major_version() { return VMAJOR; }

   431   int get_minor_version() { return VMINOR; }

   432 

   433   $ cat Makefile

   434   %.o: %.c

   435       $(CC) -DVMAJOR=$(VMAJOR) -DVMINOR=$(VMINOR) -o $@ $<