Hi ! This is probably a newby question but I can't find the anwser ... I have 2 files : a.new & a.old a.new : compiled today a.old : compiled some years ago, on another system jack@cixci:/$ file a.new a.new: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.15, not stripped jack@cixci:/$ file a.old a.old: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.0.0, not stripped Is there a way to build again the same "a.old" --> on my actual system, build the program for the old system ? Thanks for your help, Jack