Which version of glibc?
I get asked this ridiculous question at least once a month at work, due to the proprietary software that we use. I'm tired of googling for the answer, which I can never remember, so here it is:
#include <stdio.h>
#include <gnu/libc-version.h>
int main (void) { puts (gnu_get_libc_version ()); return 0; }