#include <fontconfig.h>
int FcStrCmpIgnoreCase (const FcChar8 *s1, const FcChar8 *s2);
Returns the usual <0, 0, >0 result of comparing s1 and s2. This test is case-insensitive in the ASCII range and will operate properly with UTF8 encoded strings, although it does not check for well formed strings.
Fontconfig version 2.3.2