- *
- * @return string Returns the full path of the downloaded file or a PEAR
- * error on failure. If the error is caused by
- * socket-related errors, the error object will
- * have the fsockopen error code available through
- * getCode().
+ * @param false|string|array $lastmodified header values to check against
+ * for caching
+ * use false to return the header
+ * values from this download
+ * @param false|array $accept Accept headers to send
+ * @param false|string $channel Channel to use for retrieving
+ * authentication
+ *
+ * @return mixed Returns the full path of the downloaded file or a PEAR
+ * error on failure. If the error is caused by
+ * socket-related errors, the error object will
+ * have the fsockopen error code available through
+ * getCode(). If caching is requested, then return the header
+ * values.
+ * If $lastmodified was given and the there are no changes,
+ * boolean false is returned.