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이 문서에서는 PHP 중국어 웹사이트 매뉴얼 풀어 주다
(PHP 5)
pcntl_getpriority — 获取任意进程的优先级
$pid
= getmypid()
[, int $process_identifier
= PRIO_PROCESS
]] ) pcntl_getpriority() 获取进程号为
pid
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,因此请参考您系统的getpriority(2)手册以获取详细的规范。
pid
如果没有指定,默认是当前进程的进程号。
process_identifier
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)或 PRIO_PROCESS(译注:默认值;获取进程优先级)
三者之一。
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。
此函数可能返回布尔值
FALSE
,但也可能返回等同于 FALSE
的非布尔值。请阅读 布尔类型章节以获取更多信息。应使用
===
运算符来测试此函数的返回值。
[#1] jonathan at jcdesigns dot com [2008-05-15 02:12:47]
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);
}