PHP Manual . ... Next . PHP 4 CVS only) ob_flush -- Flush (send) the output buffer . ... This function will send the contents of the output buffer (if any). If you want to further process the buffer's contents you have to call ob_get_contents() before ob_flush() as the buffer contents are discarded after ob_flush() is called. This function does not destroy the output buffer like ob_end_flush() does. See also ob_get_contents() , ob_clean() , ob_end_flush() and ob_end_clean() . ...