pthreads PECL扩展使使用线程成为可能

http://www.php.net/manual/en/book.pthreads.php

取决于你要做什么，你也可以使用curl_multi来实现它。

那么pcntl_fork呢?

检查我们的手册页的例子:PHP pcntl_fork

<?php

    $pid = pcntl_fork();
    if ($pid == -1) {
        die('could not fork');
    } else if ($pid) {
        // we are the parent
        pcntl_wait($status); //Protect against Zombie children
    } else {
        // we are the child
    }

?>

如果Pcntl_fork开启了安全模式，它将无法在web服务器环境中工作。在这种情况下，它只能在CLI版本的PHP中工作。

我知道这是一个老问题，但对于搜索的人来说，有一个用C编写的PECL扩展，现在提供了PHP多线程功能，它位于https://github.com/krakjoe/pthreads

As of the writing of my current comment, I don't know about the PHP threads. I came to look for the answer here myself, but one workaround is that the PHP program that receives the request from the web server delegates the whole answer formulation to a console application that stores its output, the answer to the request, to a binary file and the PHP program that launched the console application returns that binary file byte-by-byte as the answer to the received request. The console application can be written in any programming language that runs on the server, including those that have proper threading support, including C++ programs that use OpenMP.

一个不可靠的，肮脏的技巧是使用PHP来执行控制台应用程序，"uname"，

uname -a

and print the output of that console command to the HTML output to find out the exact version of the server software. Then install the exact same version of the software to a VirtualBox instance, compile/assemble whatever fully self-contained, preferably static, binaries that one wants and then upload those to the server. From that point onwards the PHP application can use those binaries in the role of the console application that has proper multi-threading. It's a dirty, unreliable, workaround to a situation, when the server administrator has not installed all needed programming language implementations to the server. The thing to watch out for is that at every request that the PHP application receives the console application(s) terminates/exit/get_killed.

As to what the hosting service administrators think of such server usage patterns, I guess it boils down to culture. In Northern Europe the service provider HAS TO DELIVER WHAT WAS ADVERTISED and if execution of console commands was allowed and uploading of non-malware files was allowed and the service provider has a right to kill any server process after a few minutes or even after 30 seconds, then the hosting service administrators lack any arguments for forming a proper complaint. In United States and Western Europe the situation/culture is very different and I believe that there's a great chance that in U.S. and/or Western Europe the hosting service provider will refuse to serve hosting service clients that use the above described trick. That's just my guess, given my personal experience with U.S. hosting services and given what I have heard from others about Western European hosting services. As of the writing of my current comment(2018_09_01) I do not know anything about the cultural norms of the Southern-European hosting service providers, Southern-European network administrators.