Without a real ob_gzhandler function, replacing it with an alias as currently in RC1 : what if someone then creates an ob_gzhandler function in userland ? would ob_start('ob_gzhandler') use the userland function or still the alias ? I think this is a second argument to make ob_gzhandler a real function : least surprise.
Personally, I do use ob_gzhandler directly because it's the easiest way to do chunked compressed encoding in userland. This allows me to ask for compression as late as possible, because registering an ob_start('ob_gzhandler'); may be too early for me. I do want to choose to enable compression only when the very first byte is about to be sent over the wire. Hope it helps Nicolas <?php function my_ob_handler($buffer, $mode) { // based on content-type, // do some $buffer filtering // and add some header() if (/* content-type benefits compression based on some userland rules */) { $buffer = ob_gzhandler($buffer, $mode); // benefits from gzip negotiation, chunked compression and related headers if (PHP_OUTPUT_HANDLER_START & $mode) { // play/fix with Vary: header, as sent by ob_gzhandler or before } } return $buffer; }