Posted by Chris Shiflett on 09/02/05 21:26

Rasmus Lerdorf wrote:
> Then you have configured your server to always turn on output
> buffering or your test script is bad.

I don't think it's either, but I'll let you decide. I tried a new test
with your code and some slight modifications:

<?php

header('Location: http://www.php.net/');
$fp = fopen('/tmp/log.txt', 'w');
for ($i = 0; $i < 30; $i++)
{
$str = "Count $i\n";
echo $str;
fputs($fp, $str);
sleep(1);
flush();
}

?>

Basically, I'm only looping 30 times, but I'm sleeping for a second and
flushing the buffer each time. The result is a response that looks
something like this:

HTTP/1.1 302 Found
Date: Fri, 02 Sep 2005 18:12:02 GMT
Server: Apache/1.3.33 (Debian GNU/Linux)
Location: http://www.php.net/
Transfer-Encoding: chunked
Content-Type: text/html; charset=iso-8859-1

8
Count 0

8
Count 1

8
Count 2

....

9
Count 27

9
Count 28

9
Count 29

0

This result is not buffered on the server by PHP or Apache - each of
these chunks are received about one second apart, and the headers are
received barely more than one second after the request is sent (only
because I didn't flush before the first sleep):

[2005-09-02 14:12:07] [+0.004467 seconds] HTTP Server: socket_read() ...
[2005-09-02 14:12:08] [+1.131124 seconds] > Headers Received
[2005-09-02 14:12:08] [+0.002197 seconds] > Transfer-Encoding [chunked]
[2005-09-02 14:12:08] [+0.004580 seconds] > chunk_length [8]
[2005-09-02 14:12:09] [+1.013278 seconds] > chunk_length [8]
[2005-09-02 14:12:10] [+0.972697 seconds] > chunk_length [8]

Of the three browsers I tested, none sent a request for
http://www.php.net/ until they had received the very last byte of the
response - the 0 indicating no more content. This happens a little more
than 30 seconds after the request is sent and a little more than 29
seconds after the HTTP response line and headers (including Location)
are received.

Chris

--
Chris Shiflett
Brain Bulb, The PHP Consultancy
http://brainbulb.com/

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