子进程中调用server->push函数卡住，没有错误

[linkdrone]

Please answer these questions before submitting your issue. Thanks!

1. What did you do? If possible, provide a simple script for reproducing the error.

<?php
$server = new Swoole\WebSocket\Server("127.0.0.1", 9502);

$server->on('open', function($server, $req) {
    echo "connection open: {$req->fd}\n";
});

$server->on('message', function($server, $frame) {
    echo "received message: {$frame->data}\n";
    $server->push($frame->fd, json_encode(["hello", "world"]));
});

$server->on('close', function($server, $fd) {
    echo "connection close: {$fd}\n";
});


//启动子进程
$producer = new \swoole_process(function (\swoole_process $worker) {
    //swoole_event_add()
    global $server;
    while(true)
    {
//                usleep(500);
//                Service::$server->push(1, '000');
//                $data = $worker->read();
//                var_dump(microtime(true));
        sleep(1);
        var_dump('111');
        var_dump($server->push(1, 'xxx')); //注：此处卡住，没有错误信息输出
        var_dump('222');
    }
}, false, SOCK_DGRAM);
$producer->start();

$server->start();

swoole_process::wait();

2. What did you expect to see?

希望可以知道卡住的原因或者报错信息

3. What did you see instead?
   如果是报错了希望得知错误原因，如果是卡住了，这是什么原因导致的？有木有相关文档？

4. What version of Swoole are you using (show your php --ri swoole)?

swoole

Swoole => enabled
Author => Swoole Team <team@swoole.com>
Version => 4.4.12
Built => Nov 25 2019 14:29:03
coroutine => enabled
kqueue => enabled
rwlock => enabled
http2 => enabled
pcre => enabled
zlib => 1.2.11
mysqlnd => enabled
async_redis => enabled

Directive => Local Value => Master Value
swoole.display_errors => On => On
swoole.enable_coroutine => On => On
swoole.enable_library => On => On
swoole.enable_preemptive_scheduler => Off => Off
swoole.unixsock_buffer_size => 262144 => 262144
swoole.use_shortname => On => On

5. What is your machine environment used (including version of kernel & php & gcc) ?

macos

[twose]

https://wiki.swoole.com/wiki/page/390.html

[linkdrone]

这个卡住的原因是？有相关的文档说明吗？

[linkdrone]

独立启动的Process是不能正常使用$server对象的？ @twose

[twose]

不是卡住了 你的未定义行为造成了程序崩溃

[linkdrone]

程序崩溃的话请问怎样可以看到对应的崩溃日志？我在控制台和swoole.log日志文件里面都没发现有错误日志输出 @twose

[twose]

修复于 1d56967

这个等级的崩溃（空指针coredump）没有日志，由操作系统记录

[linkdrone]

好的 谢谢