ax_sys_largefile_sensitive
==========================

Synopsis
********

     AX_SYS_LARGEFILE_SENSITIVE

Description
***********

Check whether the current system is sensitive to -Ddefines making off_t having different types/sizes. Automatically define a config.h symbol LARGEFILE_SENSITIVE if that is the case, otherwise leave everything as is.

This macro builds on top of AC_SYS_LARGEFILE to detect whether special options are neede to make the code use 64bit off_t - in many setups this will also make the code use 64bit off_t immediatly.

The common use of a LARGEFILE_SENSITIVE config.h-define is to rename exported functions, usually adding a 64 to the original function name. Such renamings are only needed on systems being both (a) 32bit off_t by default and (b) implementing large.file extensions (as for unix98).

a renaming section could look like this:

      #if defined LARGEFILE_SENSITIVE && _FILE_OFFSET_BITS+0 == 64
      #define zzip_open zzip_open64
      #define zzip_seek zzip_seek64
      #endif

for libraries, it is best to take advantage of the prefix-config.h macro, otherwise you want to export a renamed LARGEFILE_SENSITIVE in an installed header file. -> see AX_PREFIX_CONFIG_H

Source Code
***********

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

License
*******

Copyright © 2008 Guido U. Draheim guidod@gmx.de

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 3 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.