#include #include int main(int argc, char *argv[]) { size_t size = 1000000; if (argc > 1) { if (sscanf(argv[1], "%zu", &size) != 1) { printf("Not a number\n"); return 1; } } printf("size = %zu\n", size); if (malloc(size) != NULL) { printf("OK!\n"); } else { printf("NULL!\n"); } return 0; }