ax_compute_relative_paths
=========================

Synopsis
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     AX_COMPUTE_RELATIVE_PATHS(PATH_LIST)

Description
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PATH_LIST is a space-separated list of colon-separated triplets of the form 'FROM:TO:RESULT'. This function iterates over these triplets and set $RESULT to the relative path from $FROM to $TO. Note that $FROM and $TO needs to be absolute filenames for this macro to success.

For instance,

       first=/usr/local/bin
       second=/usr/local/share
       AX_COMPUTE_RELATIVE_PATHS([first:second:fs second:first:sf])
       # $fs is set to ../share
       # $sf is set to ../bin

$FROM and $TO are both eval'ed recursively and normalized, this means that you can call this macro with autoconf's dirnames like `prefix' or `datadir'. For example:

       AX_COMPUTE_RELATIVE_PATHS([bindir:datadir:bin_to_data])

AX_COMPUTE_RELATIVE_PATHS should also works with DOS filenames.

You may want to use this macro in order to make your package relocatable. Instead of hardcoding $datadir into your programs just encode $bin_to_data and try to determine $bindir at run-time.

This macro requires AX_NORMALIZE_PATH.

Source Code
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Download the latest version of ax_compute_relative_paths.m4 (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_compute_relative_paths.m4) or browse the macro's revision history (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_compute_relative_paths.m4).

License
*******

Copyright © 2008 Alexandre Duret-Lutz adl@gnu.org

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 <http://www.gnu.org/licenses/>.

As a special exception, the respective Autoconf Macro's copyright owner gives unlimited permission to copy, distribute and modify the configure scripts that are the output of Autoconf when processing the Macro. You need not follow the terms of the GNU General Public License when using or distributing such scripts, even though portions of the text of the Macro appear in them. The GNU General Public License (GPL) does govern all other use of the material that constitutes the Autoconf Macro.

This special exception to the GPL applies to versions of the Autoconf Macro released by the Autoconf Archive. When you make and distribute a modified version of the Autoconf Macro, you may extend this special exception to the GPL to apply to your modified version as well.