rem: printf("error opening %s : %s (%d)\n", name, strerror(cur_fd), cur_fd);
add: printf("error opening %s : %s (%d)\n", name, fs_strerror(cur_fd), cur_fd);
context: do_open(int argc, char **argv){    char name[64];    if (cur_fd >= 0)        do_close(0, NULL);    if (argc < 2)        make_random_name(name, sizeof(name));    else        sprintf(name, "/myfs/%s", &argv[1][0]);    cur_fd = sys_open(1, -1, name, O_RDWR, MY_S_IFREG, 0);    if (cur_fd < 0) {        printf("error opening %s : %s (%d)\n", name, strerror(cur_fd), cur_fd);    	return cur_fd;    } else {        printf("opened: %s\n", name);		return 0;    }}