Calling ob_flush() and flush(), yet browser doesn't show any output until script finishes

Question

Hi Please View Below Code :

\\n\";
for( $i = 0 ; $i < 10 ; $i++ )
{
    echo \"$i
\\n\";
             


        

Answer 1

You need to add a .htaccess file to disable gzip output

<IfModule mod_env.c>
    SetEnv no-gzip 1
</IfModule>

Answer 2

Some browsers need to receive at least 256 characters before they start to render. Have you already tried to stuff more output like:

echo str_repeat('&nbsp;', 50) . "$i<br />\n";

EDIT:

Under Apache/2.2.11 (Win32) DAV/2 mod_ssl/2.2.11 OpenSSL/0.9.8i PHP/5.2.9 I was able to reproduce the problem of the OP by setting

zlib.output_compression = On

Turning it off again by

zlib.output_compression = Off

made the script work as wanted.

Answer 3

It is correct. Works fine for me from CLI running PHP 5.3.3. If it's not working for you, your PHP install may have output buffering disabled.

I would also suggest putting ob_end_flush() at the end of your script to close the output buffer.

Answer 4

Try removing the call to ob_start() on your first line : there is no need for you to enable output buffering -- and it probably causes troubles, here.

I've tested your code :

• If ob_start() is called on the first line, I only see the output when the script finishes, after 10 seconds
• If I remove that call to ob_start(), then, I see one line of output every second, as soon as it's displayed on the standard output.

Answer 5

I've discovered that this was due to Apache's gzip compression being in use for my case.

To turn gzip off for the 'flushing' script only, I created a new .htaccess file in the directory where the continuous output script resides, with the following:

<IfModule mod_env.c>
    SetEnv no-gzip 1
</IfModule>

Flushing is working as expected again.

Answer 6

One sneaky issue with IE8 and flush(); is that if you're "flushing" out rows in a table. IE will only display tables when they're complete. This was my issue, and changing containers from table rows to divs solved the problem.