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

typedef struct {
  int in;
  int out;
} __attribute__
  ((packed, aligned(sizeof(int))))
    pipe_fds_t;

int
main (int argc, char **argv) {
  char **cmds = argv + 1;
  int cmds_amt = argc - 1, cmd_id = 0;
  for (; cmd_id < cmds_amt; ++cmd_id) {
    pipe_fds_t pipes;
    pipe((int *) &pipes);
    pid_t pid;
    if ((pid = fork()) < 0) {
      fprintf(stderr, "FORK ERROR");
      exit(1);
    } else if (!pid) {
      if (cmd_id != cmds_amt - 1) {
        dup2(pipes.out, 1);
      }
      close(pipes.in);
      close(pipes.out);
      execlp(cmds[cmd_id], cmds[cmd_id], NULL);
      perror("exec");
      exit(1);
    } else {
      dup2(pipes.in, 0);
      close(pipes.in);
      waitpid(pid, NULL, 0);
      close(pipes.out);
    }
  }
  return 0;
}