When an HTTP server is building a response it ultimately has to end up with a length value in the header for the document. Thus the document cannot be sent until it is complete and the content-length is known.

The NPH (non-parsed header) does not need the content-length header before the document can be parsed by the browser.

BUT - and isn't there always a BUT

NPH is now pretty dated technology. The NPH script means that you have to craft the entire header yourself and send it. NPH means that the server does not parse the headers you pass - it just passes yours on. However, some HTML elements are not able to be rendered until they are completely available to the browser - tablesbeing one example. Part of a table cannot be rendered until the entire table is transferred. Generally speaking - using a refresh or some JavaAcript will be more reliable.

jdtoronto