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  if ((*pid = fork()) == 0)
  {
   /*
    * Child process goes here; update stderr as needed...
    */

    if (errfd != 2)
    {
      if (errfd < 0)
        errfd = open("/dev/null", O_WRONLY);

      if (errfd != 2)
      {
        dup2(errfd, 2);
  close(errfd);
      }
    }

   /*
    * Put this process in its own process group so that we can kill any child
    * processes it creates.
    */

#ifdef HAVE_SETPGID
    if (!RunUser && setpgid(0, 0))
      exit(errno + 100);
#else
    if (!RunUser && setpgrp())
      exit(errno + 100);
#endif /* HAVE_SETPGID */

   /*
    * Update the remaining file descriptors as needed...
    */

    if (infd != 0)
    {
      if (infd < 0)
        infd = open("/dev/null", O_RDONLY);

      if (infd != 0)
      {
        dup2(infd, 0);
	close(infd);
      }
    }

    if (outfd != 1)
    {
      if (outfd < 0)
        outfd = open("/dev/null", O_WRONLY);

      if (outfd != 1)
      {
        dup2(outfd, 1);
	close(outfd);
      }
    }

    if (backfd != 3 && backfd >= 0)
    {
      dup2(backfd, 3);
      close(backfd);
      fcntl(3, F_SETFL, O_NDELAY);
    }

    if (sidefd != 4 && sidefd >= 0)
    {
      dup2(sidefd, 4);
      close(sidefd);
      fcntl(4, F_SETFL, O_NDELAY);
    }

   /*
    * Change the priority of the process based on the FilterNice setting.
    * (this is not done for root processes...)
    */

    if (!root)
      nice(FilterNice);

   /*
    * Reset group membership to just the main one we belong to.
    */

    if (!RunUser && setgid(Group))
      exit(errno + 100);

    if (!RunUser && setgroups(1, &Group))
      exit(errno + 100);

   /*
    * Change user to something "safe"...
    */

    if (!RunUser && user && setuid(user))
      exit(errno + 100);

   /*
    * Change umask to restrict permissions on created files...
    */

    umask(077);

   /*
    * Unblock signals before doing the exec...
    */

#ifdef HAVE_SIGSET
    sigset(SIGTERM, SIG_DFL);
    sigset(SIGCHLD, SIG_DFL);
    sigset(SIGPIPE, SIG_DFL);
#elif defined(HAVE_SIGACTION)
    memset(&action, 0, sizeof(action));

    sigemptyset(&action.sa_mask);
    action.sa_handler = SIG_DFL;

    sigaction(SIGTERM, &action, NULL);
    sigaction(SIGCHLD, &action, NULL);
    sigaction(SIGPIPE, &action, NULL);
#else
    signal(SIGTERM, SIG_DFL);
    signal(SIGCHLD, SIG_DFL);
    signal(SIGPIPE, SIG_DFL);
#endif /* HAVE_SIGSET */

    cupsdReleaseSignals();

   /*
    * Execute the command; if for some reason this doesn't work, log an error
    * exit with a non-zero value...
    */

    if (envp)
      execve(exec_path, argv, envp);
    else
      execv(exec_path, argv);

    exit(errno + 100);
  }
  else if (*pid < 0)
  {
   /*
    * Error - couldn't fork a new process!
    */

    cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to fork %s - %s.", command,
                    strerror(errno));

    *pid = 0;
  }
  else
  {
    if (!process_array)
      process_array = cupsArrayNew((cups_array_func_t)compare_procs, NULL);
 
    if (process_array)
    {
      if ((proc = calloc(1, sizeof(cupsd_proc_t) + strlen(command))) != NULL)
      {
        proc->pid    = *pid;
	proc->job_id = job ? job->id : 0;
	_cups_strcpy(proc->name, command);

	cupsArrayAdd(process_array, proc);
      }
    }
  }