pclose

(PHP 4, PHP 5, PHP 7, PHP 8)

pclose — 关闭进程文件指针

说明

pclose(resource $handle): int

关闭用 popen() 打开的指向管道的文件指针。

参数

handle: 文件指针必须有效，且必须是成功调用 popen() 所返回的。

返回值

返回运行的进程的终止状态。发生错误时会返回 -1。

范例

示例 #1 pclose() 例子


<?php
$handle = popen('/bin/ls', 'r');
pclose($handle);
?>

注释

注意: Unix Only:
proc_close() is internally implemented using the waitpid(3) system call. To obtain the real exit status code the pcntl_wexitstatus() function should be used.

参见

popen() - 打开进程文件指针

add a note

User Contributed Notes 4 notes

down

Uwe Ohse ¶

6 years ago


Regarding the return value:
"Returns the termination status of the process that was run. In case of an error then -1 is returned. "
and the note about the exit status: "pclose() is internally implemented using the waitpid(3) system call. To obtain the real exit status code the pcntl_wexitstatus() function should be used."

The documentation of the return value is, at best, misleading. The function returns, as does proc_close():
* -1 on error,
* WEXITSTATUS(status) if WIFEXITED(status) is true, or 
* status if WIFEXITED(status) is false,
where status is the status parameter of waitpid().

This makes it impossible to differentiate between a relatively normal exit or a termination by signal, and reduces the value of the proc_close return code to a binary one (ok / something broke).

This can be seen in proc_open_rsrc_dtor() in ext/standard/proc_open.c (PHP 5.4.44, 5.6.12). 

The note advising the use of pcntl_wexitstatus is plain wrong. One cannot use pcntl_wexitstatus because it already has been used.

down

vdweij at mailsurf dot com ¶

19 years ago


As I understand pclose will return 0 (on every platform) in case popen could not execute the specified command.

Since popen only returns the status wether it was able to send a command and not wether it was succesfully executed. Only the returned value of pclose can be used to check wether a command could be executed.

down

Mike ¶

14 years ago


The termination status, as pointed out in another note, is not the same as the exit status from the process. However, something like "pclose($fp)/256" is not the correct way to extract the exit status, since this uses system- and version-specific knowledge of where in the termination status the exit status is stored. (Also, the process may not even have exited normally, so it may not have an exit status at all.)

Instead, the functions pcntl_wifexited() and pcntl_wexitstatus() should be used. They are wrappers for the C macros WIFEXITED() and WEXITSTATUS() that are designed for determining whether the process had an exit status and what that status was, respectively.

down

kcross at nssolutions dot com ¶

18 years ago


Somewhere between 4.1.1 and 4.2.3, the return value from pclose changed.

The exit status used to be in the second byte, so that the status would be (pclose($fp)/256).

It is now in the low-order byte, so the status is just pclose($fp).

Be careful.

add a note

官方地址：https://www.php.net/manual/en/function.pclose.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 JAVA NoSQL 数据库面试 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 array_multisort() 多字段排序 PHPMailer设置utf8 PHPMailer字符集CharSet ADORecordSet对象 adodb手册 PHP 8.1 [鸟哥]PHP_INT_MIN 和 -9223372036854775808 opcache预加载 Composer的Packagist资源 mysql面试题 [鸟哥]PHP FFI详解 - 一种全新的PHP扩展方式 PHP7添加redis扩展 PHP mkdir()写出来的权限与mode值不符合 Packagist / Composer 中国全量镜像 php中几种注释规范利用php soap实现web service PHP获取指定函数定义在哪个文件中及行号

略微加速

PHP官方手册 - 互联网笔记

pclose

说明

参数

返回值

范例

注释

参见

User Contributed Notes 4 notes