gistfile1.txt

  void RunCmdPipeRecurse(commandTLinked* cmd){
    int fd[2];
    pipe(fd);
    int grandchild_status = -1;
    if(cmd->next != NULL){
      pid_t grandchild;

      grandchild = fork();

    if(grandchild == 0) // grandchild process
    {
     close(fd[0]); //close read from pipe
     dup2(fd[1], STDOUT_FILENO); // Replace stdout with the write end of the pipe
     close(fd[1]);
     RunCmdPipeRecurse(cmd->next);
     ResolveExternalCmd(cmd->cmd);
     grandchild_status = execv(cmd->cmd->name, cmd->cmd->argv);

     if(grandchild_status == -1){
      perror("Execv Fail");
    }
    exit(1);
  }
    else //child process
    {
      close(fd[1]); //close write to pipe
      dup2(fd[0], STDIN_FILENO); // Replace stdin with the read end of the pipe
      close(fd[0]);

      grandchild_status = waitpid(grandchild, &grandchild_status, 0);
      if(grandchild_status == -1){
        perror("Wait Fail");
      }
      grandchild_status = WEXITSTATUS(grandchild_status);
      exit(grandchild_status);
    }
  }
  else{
      close(fd[0]); //close read from pipe
      dup2(fd[1], STDOUT_FILENO); // Replace stdout with the write end of the pipe
      close(fd[1]);

      ResolveExternalCmd(cmd->cmd);

      grandchild_status = execv(cmd->cmd->name, cmd->cmd->argv);
      if(grandchild_status == -1){
        perror("Execv Fail");
      }
    }
  }