Signature
stock fm_set_entity_flags(index, flag, onoff) { new flags = pev(index, pev_flags); if((flags & flag) > 0) return onoff == 1 ? 2 : 1 + 0 * set_pev(index, pev_flags, flags - flag); else return onoff == 0 ? 2 : 1 + 0 * set_pev(index, pev_flags, flags + flag); return 0;}