Home  >  Article  >  Backend Development  >  How to solve runtime error PHP multi-process problem solving

How to solve runtime error PHP multi-process problem solving

WBOY
WBOYOriginal
2016-07-29 08:40:151534browse

Moreover, if the input data is illegal and the script does not detect it, resulting in abort, it will also make you very unhappy.
Then? What should I do?
Haha, don’t worry, multi-process will help you!
Then, why is this?
Advantages:
1. When using multiple processes, the kernel will be responsible for recycling resources after the child process ends.
2. When using multiple processes, the abnormal exit of the child process will not cause the entire process Thread to exit. The parent process will also have the opportunity to rebuild the process.
3. A resident main process is only responsible for task distribution, and the logic is clearer.
Then, how to do it?
Next, we use the POSIX and Pcntl series functions provided by PHP to implement a PHP command parser, and the main process is responsible for accepting users Enter, then fork the child process to execute, and be responsible for echoing the end status of the child process.
The code is as follows, I have added comments. If there is anything you don’t understand, you can read the relevant functions in the manual, or reply to the message.

Copy the code The code is as follows:


#!/bin/env php
/**A example denoted muti-process application in php
* @filename fork.php
* @touch date Wed 10 Jun 2009 10:25:51 PM CST
* @author Laruence
* @license http://www.zend.com/license/3_0.txt PHP License 3.0
* @version 1.0.0
*/
/**Make sure this function can only be run in SHELL*/
if
(substr(php_sapi_name(), 0, 3) !== 'cli')
{
die("This Programe can only be run in CLI mode");
}
/**Turn off the maximum execution event limit. In CLI mode, this statement is actually unnecessary.*/
set_time_limit(0);
$pid = posix_getpid( ); //Get the main process ID
$user = posix_getlogin(); //Get the user name
echo
<<USAGE: [command | expression]
input php code to execute by fork a new process
input quit to exit
Shell Executor version 1.0.0 by laruence
EOD;
while
(true)
{
$prompt = "n{$user}$ ";
$input = readline($prompt);
readline_add_history ($input);
if
($input == 'quit')
{
break;
}
process_execute($input . ';');
}
exit(0);
function
process_execute($input )
{
$pid = pcntl_fork(); //Create sub-process
if
($pid == 0)
{//Sub-process
$pid = posix_getpid();
echo
"* Process {$pid} was created, and Executed:nn";
eval($input); //Parse command
exit;
}
else
{//Main process
$pid = pcntl_wait($status, WUNTRACED); //Get child process End status
if
(pcntl_wifexited($status))
{
echo
"nn* Sub process: {$return['pid']} exited with {$status}";
}
}
}

The above has introduced how to solve runtime errors and solve problems in PHP multi-process, including how to solve runtime errors. I hope it will be helpful to friends who are interested in PHP tutorials.

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn