typedef __SIZE_TYPE__ size_t; void *memmove (void *dest, const void *src, size_t count); size_t strlen (const char *s); int foo (char *param, char *val) { if (val) { if (val == param + strlen (param) + 1) val[-1] = '='; else if (val == param + strlen (param) + 2) { val[-2] = '='; memmove (val - 1, val, strlen (val) + 1); val--; } } return 0; }