php Pthread 线程 互斥锁

在进行并发操作时,会导致共享数据的完整性的问题,要加入锁,在任意时刻只有一个线程访问该对象
在PHP中定义专门用于线程同步控制的mutex的函数, pthreads v3 中已经将 Mutex 类移除。
简单的计数器程序，有加锁和没有加锁的情况,pthreads v3使用synchronized同步处理

 

<?php
class CounterThread extends Thread {
    public $counter = 0;
    public $handle;
    public $mutex;
    public function __construct($handle,$mutex = null){
        $this->mutex = $mutex;
    }
    public function run() {
        //加锁
        if($this->mutex){
            $locked=Mutex::lock($this->mutex);
        }
        $this->handle = fopen("/tmp/counter.txt", "w+");
        $this->counter = intval(fgets($this->handle));
        $this->counter++;
        rewind($this->handle);
        fwrite($this->handle, $this->counter."\r\n");
        printf("Thread #%lu says: %s\n", $this->getThreadId(),$this->counter);
        $this->close();
        if($this->mutex){
            //释放锁
            Mutex::unlock($this->mutex);
        }
    }
    public function close()
    {
        print_r(fclose( $this->handle));echo PHP_EOL;
    }
}
$handle=fopen("/tmp/counter.txt", "w+");
//没有互斥锁
for ($i=0;$i<10;$i++){
    $threads[$i] = new CounterThread($handle);
    $threads[$i]->start();
    sleep(1);
}

//创建一个互斥锁 
//参数设置true，表示创建互斥量之后，立即加锁，
$mutex = Mutex::create();
for ($i=0;$i<10;$i++){
    $threads[$i] = new CounterThread($handle,$mutex);
    $threads[$i]->start();
    sleep(1);
}
//销毁互斥量
Mutex::destroy($mutex);

/*
Mutex::unlock($mutex);
for ($i=0;$i<50;$i++){
    $threads[$i]->join();
}
Mutex::destroy($mutex);
*/

?>