What should I do if the php pcntl_fork process does not die?

php pcntl_fork process does not die solution: 1. Open the corresponding PHP code file; 2. Check the php multi-thread processing code; 3. Pass "public function installSignal(){pcntl_signal(SIGTERM, [$ This, 'sigHandle'])...};" can be used to install the signal processor.

The operating environment of this tutorial: Windows 7 system, PHP version 8.1, Dell G3 computer.

php What should I do if the pcntl_fork process does not die?

Problem description

The first time I used PHP multi-threaded processing tasks caused a zombie process problem, the reason was that the child process did not send the end signal and the parent process did not wait. The end of the child process

Understanding

• pcntl_fork returns -1: Failed to start the process 0: Indicates that the current child process is greater than zero: The current parent Process, the return value is the child process pid

• After the fork child process code is executed, it must exit() and send an end signal. Otherwise, continue to fork the child process. Get the parent process pid = posix_getppid(), current pid = getmypid() or posix_getpid()

• The parent process is best to wait for the child process to finish executing and recycle the child process through pcntl_wait(), pcntl_waitpid( ) to implement synchronous and asynchronous waiting for the parent process to loop the child process:

$result = pcntl_waitpid($pid_, $status, WNOHANG);
 
$result等于-1时代表子进程结束

• The function of the signal processor is to process the end signal returned by the child process

public function run()
    {
        $this->installSignal();
        // 获取当前pid   getmypid()
        $current_pid = posix_getpid();
        // dump('当前pid:'.$current_pid);
        cli_set_process_title('设置process_title');
        $pids = [];
        for($i = 0; $i < $this->forks; $i ++){
            $pid = pcntl_fork();
            if($pid == -1){
                die(&#39;进程开启失败&#39;);
            }else if($pid){
                // 父进程得到子进程pid
                dump(&#39;父进程&#39;);
                dump(&#39;父进程得到子进程pid&#39;.$pid);
                $pids[] = $pid;
            }else{
                dump(&#39;子进程&#39;);
                dump(&#39;父进程pid-&#39;.posix_getppid());
                // 子进程
                dump("第{$i}个进程");
                sleep(10);
                dump("第{$i}个进程：等待10s");
                // 发送结束信号
                // exit(-1);
                // posix_kill(getmypid(), SIGKILL);
                posix_kill(getmypid(), SIGHUP);
            }
        }
        // 父进程等待子进程执行结束
        while($pids){
            foreach($pids as $k => $pid_){
                dump(&#39;父进程不阻塞-等待子进程结束&#39;);
                $result = pcntl_waitpid($pid_, $status, WNOHANG);
                dump($result);
                if($result === -1){
              dump(&#39;子进程返回状态&#39;.$status);
       unset($pids[$k]);
                }
        }
    }
    /**
     * 信号处理器
     */
    public function sigHandle($signo)
    {
        switch ($signo) {
            case SIGTERM:
                // 处理SIGTERM信号
                dump(&#39;处理SIGTERM信号&#39;);
                exit;
                break;
            case SIGHUP:
                    //处理SIGHUP信号
                dump(&#39;处理SIGHUP信号&#39;);
                exit(SIGHUP);
                break;
            case SIGUSR1:
                dump(&#39;处理SIGUSR1信号&#39;);
                break;
            default:
                // 处理所有其他信号
        }
    }
    /**
     * 安装信号处理器
     *
     */
    public function installSignal()
    {
        pcntl_signal(SIGTERM, [$this, &#39;sigHandle&#39;]);
        pcntl_signal(SIGHUP, [$this,&#39;sigHandle&#39;]);
        pcntl_signal(SIGUSR1, [$this,&#39;sigHandle&#39;]);
    }

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