In most situations, calling
AC_OUTPUT is sufficient to produce
makefiles in subdirectories. However, configure scripts
that control more than one independent package can use
AC_CONFIG_SUBDIRS to run configure scripts for other
packages in subdirectories.
if test "x$package_foo_enabled" = xyes; then my_subdirs="$my_subdirs foo" fi AC_CONFIG_SUBDIRS([$my_subdirs])
because this prevents ‘./configure --help=recursive’ from displaying the options of the package
foo. Instead, you should write:if test "x$package_foo_enabled" = xyes; then AC_CONFIG_SUBDIRS([foo]) fi
If a given dir is not found at configure run time, a warning is reported; if the subdirectory is optional, write:if test -d "$srcdir/foo"; then AC_CONFIG_SUBDIRS([foo]) fi
If a given dir contains configure.gnu, it is run instead of configure. This is for packages that might use a non-Autoconf script Configure, which can't be called through a wrapper configure since it would be the same file on case-insensitive file systems. Likewise, if a dir contains configure.in but no configure, the Cygnus configure script found by
The subdirectory configure scripts are given the same command line options that were given to this configure script, with minor changes if needed, which include:
- adjusting a relative name for the cache file;
- adjusting a relative name for the source directory;
- propagating the current value of
$prefix, including if it was defaulted, and if the default values of the top level and of the subdirectory configure differ.
This macro also sets the output variable
subdirsto the list of directories ‘dir ...’. Make rules can use this variable to determine which subdirectories to recurse into.
This macro may be called multiple times.