4.5 Outputting Files

Every Autoconf script, e.g., ‘configure.ac’, should finish by calling AC_OUTPUT. That is the macro that generates and runs ‘config.status’, which in turn creates the makefiles and any other files resulting from configuration. This is the only required macro besides AC_INIT (see section Finding configure Input).

Macro: AC_OUTPUT

Generate ‘config.status’ and launch it. Call this macro once, at the end of ‘configure.ac’.

‘config.status’ performs all the configuration actions: all the output files (see Creating Configuration Files, macro AC_CONFIG_FILES), header files (see Configuration Header Files, macro AC_CONFIG_HEADERS), commands (see Running Arbitrary Configuration Commands, macro AC_CONFIG_COMMANDS), links (see Creating Configuration Links, macro AC_CONFIG_LINKS), subdirectories to configure (see Configuring Other Packages in Subdirectories, macro AC_CONFIG_SUBDIRS) are honored.

The location of your AC_OUTPUT invocation is the exact point where configuration actions are taken: any code afterwards is executed by configure once config.status was run. If you want to bind actions to config.status itself (independently of whether configure is being run), see Running Arbitrary Configuration Commands.

Historically, the usage of AC_OUTPUT was somewhat different. See section Obsolete Macros, for a description of the arguments that AC_OUTPUT used to support.

If you run make in subdirectories, you should run it using the make variable MAKE. Most versions of make set MAKE to the name of the make program plus any options it was given. (But many do not include in it the values of any variables set on the command line, so those are not passed on automatically.) Some old versions of make do not set this variable. The following macro allows you to use it even with those versions.

Macro: AC_PROG_MAKE_SET

If the Make command, $MAKE if set or else ‘make’, predefines $(MAKE), define output variable SET_MAKE to be empty. Otherwise, define SET_MAKE to a macro definition that sets $(MAKE), such as ‘MAKE=make’. Calls AC_SUBST for SET_MAKE.

If you use this macro, place a line like this in each ‘Makefile.in’ that runs MAKE on other directories:

@SET_MAKE@