C: preprocess only ifdefs

angustia · 12-18-2006, 11:08 AM

hi

i've got a big ugly c code, full of

#ifdef WIN32
#elif LINUX
#else
#endif

i would like to process the code to apply only #ifdefs, to extract the LINUX version fo the code.

i tried cpp but it adds more code from the #include files and replaces constants with their values, losing their meanings.

there's some tool for that? or something with M4?

thanks in advance

Harmaa Kettu · 12-18-2006, 01:19 PM

There is unifdef command, which has gained a lot of publicity recently because it is used by the new headers_install target of Linux kernel makefiles. If your distro does not have it packaged, you can get it from here. See the manpage for usage.

angustia · 12-18-2006, 02:30 PM

deleted

i realised that the problem is elsewhere...

unifdef can work with segments of the source file but with the whole file it seems fail and nothing get changed... and there's no error message