9.1 Executable Scripts

It is possible to define and install programs that are scripts. Such programs are listed using the SCRIPTS primary name. When the script is distributed in its final, installable form, the Makefile usually looks as follows:

     # Install my_script in $(bindir) and distribute it.
     dist_bin_SCRIPTS = my_script

Script are not distributed by default; as we have just seen, those that should be distributed can be specified using a dist_ prefix as with other primaries.

Scripts can be installed in bindir, sbindir, libexecdir, or pkgdatadir.

Scripts that need not being installed can be listed in noinst_SCRIPTS, and among them, those which are needed only by ‘make check’ should go in check_SCRIPTS.

When a script needs to be built, the Makefile.am should include the appropriate rules. For instance the automake program itself is a Perl script that is generated from automake.in. Here is how this is handled:

     bin_SCRIPTS = automake
     CLEANFILES = $(bin_SCRIPTS)
     EXTRA_DIST = automake.in
     
     do_subst = sed -e 's,[@]datadir[@],$(datadir),g' \
                 -e 's,[@]PERL[@],$(PERL),g' \
                 -e 's,[@]PACKAGE[@],$(PACKAGE),g' \
                 -e 's,[@]VERSION[@],$(VERSION),g' \
                 ...
     
     automake: automake.in Makefile
             $(do_subst) < $(srcdir)/automake.in > automake
             chmod +x automake

Such scripts for which a build rule has been supplied need to be deleted explicitly using CLEANFILES (see Clean), and their sources have to be distributed, usually with EXTRA_DIST (see Dist).

Another common way to build scripts is to process them from configure with AC_CONFIG_FILES. In this situation Automake knows which files should be cleaned and distributed, and what the rebuild rules should look like.

For instance if configure.ac contains

     AC_CONFIG_FILES([src/my_script], [chmod +x src/my_script])

to build src/my_script from src/my_script.in, then an src/Makefile.am to install this script in $(bindir) can be as simple as

     bin_SCRIPTS = my_script
     CLEANFILES = $(bin_SCRIPTS)

There is no need for EXTRA_DIST or any build rule: Automake infers them from AC_CONFIG_FILES (see Requirements). CLEANFILES is still useful, because by default Automake will clean targets of AC_CONFIG_FILES in distclean, not clean.

Although this looks simpler, building scripts this way has one drawback: directory variables such as $(datadir) are not fully expanded and may refer to other directory variables.