"Transfer-Encoding: chunked" header in PHP

Question

i want to add Transfer-Encoding: chunked header to the file that i'm outputing (its just generated plain text), but when i add:

header("Transfer-Encoding: chunked");
flush();

the browser doesn't want to open the file.

The webpage at ... might be temporarily down or it may have moved permanently to a new web address.

what i need to do for it to work?

Answer 1

You need to send the Content-Length with every chunk you send. Look at Wikipedia for a first impression, how a chunked encoding looks like. Its not that trivial and in many cases its oversized.

Update: First you send the headers, because they must always send before any content (also with chunked encoding). Then you send (for every chunk) the size (in hexadecimal) followed by the content. Remember flush() after every chunk. At last you must send a zero-size chunk to make sure, that the connection get closed properly.

Its not tested, but something like this

header("Transfer-Encoding: chunked");
echo "5\r\n";
echo "Hello";
echo "\r\n\r\n";
flush();
echo "5\r\n";
echo "World";
echo "\r\n";
flush();
echo "0\r\n\r\n";
flush();