PHP Manual: Tells whether the filename is writable

Description

bool is_writable(string $filename)

Returns true if the filename exists and is writable. The filename argument may be a directory name allowing you to check if a directory is writable.

Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody').

Parameters

filename: The filename being checked.

Return Values

Returns true if the filename exists and is writable.

Errors/Exceptions

Upon failure, an E_WARNING is emitted.

Examples

Example #1 is_writable example

<?php
$filename = 'test.txt';
if (is_writable($filename)) {
    echo 'The file is writable';
} else {
    echo 'The file is not writable';
}
?>

Notes

Note: The results of this function are cached. See clearstatcache for more details.

Tip

As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to Supported Protocols and Wrappers to determine which wrappers support stat family of functionality.