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posix_access

(PHP 5 >= 5.1.0RC1)

posix_access --  Determine accessibility of a file

说明

bool posix_access ( string file [, int mode] )

posix_access() checks the user's permission of a file.

注: 当安全模式被激活时，PHP 将检查被操作的文件或者目录是否与正在执行的脚本有相同的 UID（所有者）。

参数

file

The name of the file to be tested.

mode

A mask consisting of one or more of POSIX_F_OK, POSIX_R_OK, POSIX_W_OK and POSIX_X_OK. Defaults to POSIX_F_OK.

POSIX_R_OK, POSIX_W_OK and POSIX_X_OK request checking whether the file exists and has read, write and execute permissions, respectively. POSIX_F_OK just requests checking for the existence of the file.

返回值

如果成功则返回 TRUE，失败则返回 FALSE。

范例

例子 1. posix_access() example

This example will check if the $file is readable and writable, otherwise will print an error message.

<?php

$file = 'some_file';

if (posix_access($file, POSIX_R_OK | POSIX_W_OK)) {
    echo 'The file is readable and writable!';

} else {
    $error = posix_get_last_error();

    echo "Error $error: " . posix_strerror($error);
}

?>

参见

posix_get_last_error()
posix_strerror()



后退起点前进
POSIX Functions上一级posix_ctermid