File: autoconf.info,  Node: Configuration Commands,  Next: Configuration Links,  Prev: Configuration Headers,  Up: Setup

4.10 Running Arbitrary Configuration Commands
=============================================

You can execute arbitrary commands before, during, and after
‘config.status’ is run.  The three following macros accumulate the
commands to run when they are called multiple times.
‘AC_CONFIG_COMMANDS’ replaces the obsolete macro ‘AC_OUTPUT_COMMANDS’;
see *note Obsolete Macros::, for details.

 -- Macro: AC_CONFIG_COMMANDS (TAG..., [CMDS], [INIT-CMDS])
     Specify additional shell commands to run at the end of
     ‘config.status’, and shell commands to initialize any variables
     from ‘configure’.  Associate the commands with TAG.  Since
     typically the CMDS create a file, TAG should naturally be the name
     of that file.  If needed, the directory hosting TAG is created.
     The TAG should not contain shell metacharacters.  *Note Special
     Chars in Variables::.  This macro is one of the instantiating
     macros; see *note Configuration Actions::.

     Here is an unrealistic example:
          fubar=42
          AC_CONFIG_COMMANDS([fubar],
                             [echo this is extra $fubar, and so on.],
                             [fubar=$fubar])

     Here is a better one:
          AC_CONFIG_COMMANDS([timestamp], [date >timestamp])

   The following two macros look similar, but in fact they are not of
the same breed: they are executed directly by ‘configure’, so you cannot
use ‘config.status’ to rerun them.

 -- Macro: AC_CONFIG_COMMANDS_PRE (CMDS)
     Execute the CMDS right before creating ‘config.status’.

     This macro presents the last opportunity to call ‘AC_SUBST’,
     ‘AC_DEFINE’, or ‘AC_CONFIG_ITEMS’ macros.

 -- Macro: AC_CONFIG_COMMANDS_POST (CMDS)
     Execute the CMDS right after creating ‘config.status’.