SyncSemaphore::__construct

(PECL sync >= 1.0.0)

SyncSemaphore::__construct — Constructs a new SyncSemaphore object

说明

public SyncSemaphore::__construct(string $name = ?, int $initialval = 1, bool $autounlock = true)

Constructs a named or unnamed semaphore.

参数

name: The name of the semaphore if this is a named semaphore object.

注意:
If the name already exists, it must be able to be opened by the current user that the process is running as or an exception will be thrown with a meaningless error message.
initialval: The initial value of the semaphore. This is the number of locks that may be obtained.
autounlock: Specifies whether or not to automatically unlock the semaphore at the conclusion of the PHP script.

警告
If an object is: A named semaphore with an autounlock of false, the object is locked, and the PHP script concludes before the object is unlocked, then the underlying semaphore will end up in an inconsistent state.

返回值

The new SyncSemaphore object.

错误／异常

An exception is thrown if the semaphore cannot be created or opened.

范例

示例 #1 SyncSemaphore::__construct() example


<?php
$semaphore = new SyncSemaphore("LimitedResource_2clients", 2);

if (!$semaphore->lock(3000))
{
    echo "Unable to lock semaphore.";

    exit();
}

/* ... */

$semaphore->unlock();
?>

参见

SyncSemaphore::lock() - Decreases the count of the semaphore or waits
SyncSemaphore::unlock() - Increases the count of the semaphore

add a note

User Contributed Notes

There are no user contributed notes for this page.

官方地址：https://www.php.net/manual/en/syncsemaphore.construct.php

有任何技术问题请点击这里网站运营推广招聘

IT PHP 编程语言 Linux 开发编程科技 Elasticsearch HTML/CSS/XML 网络数据库 JAVA 面试 NoSQL C/C++ Golang Git 算法操作系统正则表达式 Redis 互联网 MySql JavaScript 运维软件国际架构设计 Mac OS TCP/IP Excel Vim Windows Socket Oracle VR MongoDB Python 运营 MemCache 商业硬件电子娱乐设计 nginx 摄影游戏 WordPress HTTP 团建数码电器

php7 安装fileinfo扩展 preg_split — 通过一个正则表达式分隔字符串 php位值,解决 PHP 中 usort 在值相同时改变原始位置的问题 [PHP] inet_pton/inet_ntop IP地址转换函数 PHP 8.1 [鸟哥]PHP_INT_MIN 和 -9223372036854775808 adodb手册 ADORecordSet对象 opcache预加载 Composer的Packagist资源 array_multisort() 多字段排序 PHPMailer设置utf8 PHPMailer字符集CharSet mysql面试题 PHP json解析（json_decode）页面工具 [原创]诡异的php-fpm超时问题 php中几种注释规范纯php实现DES以及TripleDES加密算法 php 修改图片大小支持php7的性能采集扩展利用PHP SOAP实现WEB SERVICE

略微加速

PHP官方手册 - 互联网笔记

SyncSemaphore::__construct

说明

参数

返回值

错误／异常

范例

参见

User Contributed Notes