WordPress at a glance
function is not described

wp_is_writable() WP 3.6.0

Determine if a directory is writable.

This function is used to work around certain ACL issues in PHP primarily affecting Windows Servers.

  • See: win_is_writable()

No Hooks.

Return

true/false. Whether the path is writable.

Usage

wp_is_writable( $path );
$path(string) (required)
Path to check for write-ability.

Code of wp is writable: wp-includes/functions.php VER 5.0.3

<?php
function wp_is_writable( $path ) {
	if ( 'WIN' === strtoupper( substr( PHP_OS, 0, 3 ) ) )
		return win_is_writable( $path );
	else
		return @is_writable( $path );
}