@node ax_save_flags_with_prefix
@unnumberedsec ax_save_flags_with_prefix

@majorheading Synopsis

@smallexample
AX_SAVE_FLAGS_WITH_PREFIX(PREFIX, LIST-OF-FLAGS)
@end smallexample

@majorheading Description

For each flag in LIST-OF-FLAGS, it expands to lower-cased shell variable
with the prefix holding the flag original value.  The saved variables
can be restored by AX_RESTORE_FLAGS_WITH_PREFIX

As an example: AX_SAVE_FLAGS_WITH_PREFIX([GL], [[CFLAGS],[LIBS]])
expands to

@smallexample
  gl_saved_flag_cflags="$CFLAGS"
  gl_saved_flag_libs="$LIBS"
  CFLAGS="$GL_CFLAGS $CFLAGS"
  LIBS="$GL_LIBS $LIBS"
@end smallexample

One common use case is to define a package specific wrapper macro around
this one, and also setup other variables if needed. For example:

@smallexample
  AC_DEFUN([_AX_CHECK_GL_SAVE_FLAGS], [
    AX_SAVE_FLAGS_WITH_PREFIX([GL],[$1])
    AC_LANG_PUSH([C])
  ])
@end smallexample

@smallexample
  # pushes GL_CFLAGS and GL_LIBS to CFLAGS and LIBS
  # also set the current language to test to C
  _AX_CHECK_GL_SAVE_FLAGS([[CFLAGS],[LIBS]])
@end smallexample

@majorheading Source Code

Download the
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_save_flags_with_prefix.m4,latest
version of @file{ax_save_flags_with_prefix.m4}} or browse
@uref{http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_save_flags_with_prefix.m4,the
macro's revision history}.

@majorheading License

@w{Copyright @copyright{} 2016 Felix Chern @email{idryman@@gmail.com}}

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.

You should have received a copy of the GNU General Public License along
with this program. If not, see <https://www.gnu.org/licenses/>.

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