#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>

int
main()
{
  char  *argv[4];
  char buf;
  int fd[2];
  int nullfd = open ("/dev/null", O_RDONLY);
  pid_t  pid;

  argv[0] = "bash";
  argv[1] = "-ic";
  argv[2] = "ls";
  argv[3] = '\0';

  pipe (fd);

  pid = fork();
  if (pid == 0)
    {
      setsid ();

      close (0);
      close (1);
      close (2);
      dup2 (nullfd, 0);
      dup2 (fd[1], 1);
      dup2 (fd[1], 2);
      close (fd[1]);
      close (nullfd);
      execvp (argv[0], argv);
    }

  close (fd[1]);
  close (nullfd);
  while (read (fd[0], &buf, 1) > 0)
    write (1, &buf, 1);
  close (fd[0]);
}