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17 config.status Invocation
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The ‘configure’ script creates a file named ‘config.status’, which
actually configures, “instantiates”, the template files.  It also
records the configuration options that were specified when the package
was last configured in case reconfiguring is needed.

   Synopsis:
     ./config.status [OPTION]... [TAG]...

   It configures each TAG; if none are specified, all the templates are
instantiated.  A TAG refers to a file or other tag associated with a
configuration action, as specified by an ‘AC_CONFIG_ITEMS’ macro (*note
Configuration Actions::).  The files must be specified without their
dependencies, as in

     ./config.status foobar

not

     ./config.status foobar:foo.in:bar.in

   The supported options are:

‘--help’
‘-h’
     Print a summary of the command line options, the list of the
     template files, and exit.

‘--version’
‘-V’
     Print the version number of Autoconf and the configuration
     settings, and exit.

‘--config’
     Print the configuration settings in reusable way, quoted for the
     shell, and exit.  For example, for a debugging build that otherwise
     reuses the configuration from a different build directory BUILD-DIR
     of a package in SRC-DIR, you could use the following:

          args=`BUILD-DIR/config.status --config`
          eval SRC-DIR/configure "$args" CFLAGS=-g --srcdir=SRC-DIR

     Note that it may be necessary to override a ‘--srcdir’ setting that
     was saved in the configuration, if the arguments are used in a
     different build directory.

‘--silent’
‘--quiet’
‘-q’
     Do not print progress messages.

‘--debug’
‘-d’
     Don't remove the temporary files.

‘--file=FILE[:TEMPLATE]’
     Require that FILE be instantiated as if
     ‘AC_CONFIG_FILES(FILE:TEMPLATE)’ was used.  Both FILE and TEMPLATE
     may be ‘-’ in which case the standard output and/or standard input,
     respectively, is used.  If a TEMPLATE file name is relative, it is
     first looked for in the build tree, and then in the source tree.
     *Note Configuration Actions::, for more details.

     This option and the following ones provide one way for separately
     distributed packages to share the values computed by ‘configure’.
     Doing so can be useful if some of the packages need a superset of
     the features that one of them, perhaps a common library, does.
     These options allow a ‘config.status’ file to create files other
     than the ones that its ‘configure.ac’ specifies, so it can be used
     for a different package, or for extracting a subset of values.  For
     example,

          echo '@CC@' | ./config.status --file=-

     provides the value of ‘@CC@’ on standard output.

‘--header=FILE[:TEMPLATE]’
     Same as ‘--file’ above, but with ‘AC_CONFIG_HEADERS’.

‘--recheck’
     Ask ‘config.status’ to update itself and exit (no instantiation).
     This option is useful if you change ‘configure’, so that the
     results of some tests might be different from the previous run.
     The ‘--recheck’ option reruns ‘configure’ with the same arguments
     you used before, plus the ‘--no-create’ option, which prevents
     ‘configure’ from running ‘config.status’ and creating ‘Makefile’
     and other files, and the ‘--no-recursion’ option, which prevents
     ‘configure’ from running other ‘configure’ scripts in
     subdirectories.  (This is so other Make rules can run
     ‘config.status’ when it changes; *note Automatic Remaking::, for an
     example).

   ‘config.status’ checks several optional environment variables that
can alter its behavior:

 -- Variable: CONFIG_SHELL
     The shell with which to run ‘configure’.  It must be
     Bourne-compatible, and the absolute name of the shell should be
     passed.  The default is a shell that supports ‘LINENO’ if
     available, and ‘/bin/sh’ otherwise.

 -- Variable: CONFIG_STATUS
     The file name to use for the shell script that records the
     configuration.  The default is ‘./config.status’.  This variable is
     useful when one package uses parts of another and the ‘configure’
     scripts shouldn't be merged because they are maintained separately.

   You can use ‘./config.status’ in your makefiles.  For example, in the
dependencies given above (*note Automatic Remaking::), ‘config.status’
is run twice when ‘configure.ac’ has changed.  If that bothers you, you
can make each run only regenerate the files for that rule:
     config.h: stamp-h
     stamp-h: config.h.in config.status
             ./config.status config.h
             echo > stamp-h

     Makefile: Makefile.in config.status
             ./config.status Makefile

   The calling convention of ‘config.status’ has changed; see *note
Obsolete config.status Use::, for details.