ya.c

/* Copyright (C) 2014 Igor Gnatenko <i.gnatenko.brain@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/* Напишите на C программу myexec, которая в качестве аргумента будет принимать
 * команду и запускать её. В случае завершения запущенной команды myexec должна
 * распечатать exit_code и перезапустить пользовательскую команду. Пример:
 *
 * $ myexec sleep 42
 * sleep exited with code 0
 *
 * Reference: http://company.yandex.ru/job/vacancies/sysadm_platform.xml
 * gcc -Wall -Wextra ya.c -o ya
 */

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/wait.h>

int
main (int argc, char *argv[])
{
  pid_t pid;
  int status;

  if (argc < 2) {
      printf ("Fuck you!\n");
      return 1;
  }

  for (;;) {
    pid = fork ();
    if (pid == -1) {
      perror ("fork");
      exit (1);
    }
    if (pid == 0) {
      execvp (argv[1], &argv[1]);
    } else {
      wait (&status);
      if (WIFEXITED (status))
      {
        printf ("%s exited with return code %d\n",
                argv[1], WEXITSTATUS (status));
        if (WEXITSTATUS (status) != 0)
      }
      else if (WIFSIGNALED(status))
      {
        printf ("%s terminated by signal number %d\n",
                argv[1], WTERMSIG (status));
      }
      /* we want to give time to user for read output of program */
      sleep (1);
    }  
  }

  return 0;
}