This function is ideal for checking if a given process is running, I have seen solutions that involve running the system utilites like PS and parsing the answer, which should work fine, but this allows you to check a given PID with a single call
function CheckPID( $PID )
{
// Check if the passed in PID represents a vlaid process in the system
// Returns true if it does
// Turn off non-fatal runtime warning for a moment as we know we
// will get one if the PID does not represent a valid process
$oldErrorLevel = error_reporting(0);
error_reporting( $oldErrorLevel & ~E_WARNING );
$res = pcntl_getpriority($PID);
error_reporting( $oldErrorLevel);
return ! ( $res === false);
}
pcntl_getpriority
(PHP 5, PHP 7, PHP 8)
pcntl_getpriority — 获取任意进程的优先级
说明
pcntl_getpriority() 获取进程号为
process_id 的进程的优先级。由于不同的系统类型以及内核版本下
优先级可能不同，因此请参考系统的 getpriority（2）手册以获取详细的规范。
参数
-
process_id -
如果为
null，默认使用当前进程的进程号。 -
mode -
PRIO_PGRP（译注：获取进程组优先级）、PRIO_USER（译注：获取用户进程优先级）、PRIO_PROCESS（译注：默认值;获取进程优先级）、PRIO_DARWIN_BG或PRIO_DARWIN_THREAD之一。
返回值
pcntl_getpriority() 返回进程的优先级或在错误时返回 false。值越小代表优先级越高。
更新日志
| 版本 | 说明 |
|---|---|
| 8.0.0 |
process_id 现在可以为 null。
|
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User Contributed Notes 1 note
jonathan at jcdesigns dot com ¶
16 years ago
