php多任务程序实例解析

本文以实例简单解析了php多任务程序的实现方法，具体代码如下：

    <?php
    error_reporting(E_ALL);
    set_time_limit(0);
    /**
    * php多任务程序的实现
    * 借助proc_open
    * 其实该叫进程(process)
    * 能启动多进程，你可以使用你的想象力做你想做的了，以后再写个能用的
    * 如果你是在linux上跑php，并且启用pcntl模块后，使用pcntl函数该更好
    * 
    */
    class Thread {
      protected $_pref; // process reference
      protected static $_instance = null;
      protected $_pipes;

      private function __construct() {
        $this->_pref = 0;
      }

      public static function getInstance($file) {
        if (null == self::$_instance) {
          self::$_instance = new self;
        }

        $descriptor = array(
        0 => array("pipe", "r"),
        1 => array("pipe", "w"),
        2 => array("file", "./error-output.txt", "a"),
        );
        self::$_instance->_pref = proc_open("php -q $file", $descriptor, self::$_instance->_pipes);
        return true;
      }

      public function __destruct() {
        proc_close($this->_pref);
        $this->_pref = null;
      }
    }
    // 测试代码
    $file = __FILE__;
    if(empty($argv[1])) {
      $t2 = Thread::getInstance("$file 1");
      $t3 = Thread::getInstance("$file 2");
      $t4 = Thread::getInstance("$file 3");
      $t5 = Thread::getInstance("$file 4");
      $t5 = Thread::getInstance("$file 5");
      $t5 = Thread::getInstance("$file 6");
      $t2 = Thread::getInstance("$file 7");
      $t3 = Thread::getInstance("$file 8");
      $t4 = Thread::getInstance("$file 9");
      $t5 = Thread::getInstance("$file 10");
      $t5 = Thread::getInstance("$file 11");
      $t5 = Thread::getInstance("$file 12");
      echo "Main thread done\n";
    } else {
      $somecontent = "\r\n//~~~~~~~~~~~~-这次请求序号是：" . $argv[1];
      sleep(mt_rand(0, 3));
      $handle = fopen($file, 'a+');
      fwrite($handle, $somecontent);
    }