gistfile1.php

/**
 * Determines which Filesystem Method to use.
 * The priority of the Transports are: Direct, SSH2, FTP PHP Extension, FTP Sockets (Via Sockets class, or fsockopen())
 *
 * Note that the return value of this function can be overridden in 2 ways
 *  - By defining FS_METHOD in your <code>wp-config.php</code> file
 *  - By using the filesystem_method filter
 * Valid values for these are: 'direct', 'ssh', 'ftpext' or 'ftpsockets'
 * Plugins may also define a custom transport handler, See the WP_Filesystem function for more information.
 *
 * @since 2.5.0
 *
 * @param array $args Connection details.
 * @param string $context Full path to the directory that is tested for being writable.
 * @return string The transport to use, see description for valid return values.
 */
function get_filesystem_method($args = array(), $context = false) {
    $method = defined('FS_METHOD') ? FS_METHOD : false; //Please ensure that this is either 'direct', 'ssh', 'ftpext' or 'ftpsockets'

    if ( ! $method && function_exists('getmyuid') && function_exists('fileowner') ){
        if ( !$context )
            $context = WP_CONTENT_DIR;
        $context = trailingslashit($context);
        $temp_file_name = $context . 'temp-write-test-' . time();
        $temp_handle = @fopen($temp_file_name, 'w');
        if ( $temp_handle ) {
            if ( getmyuid() == @fileowner($temp_file_name) )
                $method = 'direct';
            @fclose($temp_handle);
            @unlink($temp_file_name);
        }
    }

    if ( ! $method && isset($args['connection_type']) && 'ssh' == $args['connection_type'] && extension_loaded('ssh2') && function_exists('stream_get_contents') ) $method = 'ssh2';
    if ( ! $method && extension_loaded('ftp') ) $method = 'ftpext';
    if ( ! $method && ( extension_loaded('sockets') || function_exists('fsockopen') ) ) $method = 'ftpsockets'; //Sockets: Socket extension; PHP Mode: FSockopen / fwrite / fread
    return apply_filters('filesystem_method', $method, $args);
}