posix_access

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

posix_access Determine accessibility of a file

说明

posix_access(string $filename, int $flags = 0): bool

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

参数

filename

The name of the file to be tested.

flags

A mask consisting of one or more of POSIX_F_OK, POSIX_R_OK, POSIX_W_OK and POSIX_X_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

成功时返回 true, 或者在失败时返回 false

示例

示例 #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