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🦉@aaa (2026-05-07 04:02:00)
これだけで簡単なシェルが作れるんだ

    while (1) {
        printf("$ ");
        char buf[256];
        fgets(buf, sizeof(buf), stdin);
        buf[strcspn(buf, "\n")] = 0; // Remove \n

        char *args[10];
        int i = 0;
        char *token = strtok(buf, " ");
        while (token && i < 9) {
            args[i++] = token;
            token = strtok(NULL, " ");
        }
        args[i] = NULL; // NULL-terminate

        if (fork() == 0) { // Child
            execvp(args[0], args);
            perror("execvp");
        } else { // Parent
            int status;
            waitpid(-1, &status, 0);
            if (status != 0) {
                printf("exited with %d\n", WEXITSTATUS(status));
            }
        }
    }

$ ls --color=auto /
bin   dev  home        initrd.img.old  lib32  lost+found  mnt  proc  run   srv  tmp  var      vmlinuz.old
boot  etc  initrd.img  lib             lib64  media       opt  root  sbin  sys  usr  vmlinuz
$ ls /root
ls: ディレクトリ '/root' を開くことが出来ません: 許可がありません
exited with 2
$ sl
execvp: No such file or directory

---Replies---

arce@arce (2026-05-07 04:44:49)
Opened up #tinyap and saw all this code stuff. Scary! :)