[imp] Dimp : "headers already sent" errors in logs

[Michael M Slusarz]

Quoting Emeric Jhelil <Emeric.Jhelil at univ-lemans.fr>:

> Hi,
> I am using horde-webmail-1.2.2 with dimp-1.1.1.
>
> I meet these kind of errors in my apache logs (they appear by two).
> - after login choosing dimp :
> [Fri Apr 03 17:52:46 2009] [error] PHP Warning:  Cannot modify header
> information - headers already sent in Unknown on line 0, referer:
> http://test/imp/login.php
> [Fri Apr 03 17:52:46 2009] [error] PHP Warning:  Cannot modify header
> information - headers already sent in Unknown on line 0, referer:
> http://test/imp/login.php
> - in dimp, selecting options or compose
> [Fri Apr 03 17:52:54 2009] [error] PHP Warning:  Cannot modify header
> information - headers already sent in Unknown on line 0, referer:
> http://test/dimp/
> [Fri Apr 03 17:52:54 2009] [error] PHP Warning:  Cannot modify header
> information - headers already sent in Unknown on line 0, referer:
> http://test/dimp/
>
> I have selected in my horde/config/conf.php : $conf['compress_pages'] =
> true;
> And they disappear if it is set to false.
>
> It seems to be linked to the flush function used in
> horde/dimp/lib/DIMP.php (header function) .
> The errors don't occur if compress_pages is set to true and the flush is
> commented out.
>
> Firebug shows these differences in the "GET dimp" http response header :
> 1) with flush and compress_pages = true :
> Vary: Accept-Language
> Transfer-Encoding: chunked
> 2) without flush and compress_pages = true :
> Vary: Accept-Language,Accept-Encoding
> Content-Encoding: gzip
> Content-Length: 5155
>
> Can it be resolved by a better configuration of my webmail ?
> Are these missing header informations harmless ?
> Is it better to comment out the flush function in
> horde/dimp/lib/DIMP.php or to let these warnings occur ?

Generally this means you have an extra space in a config file  
somewhere (not in a PHP code block).

michael

-- 
___________________________________
Michael Slusarz [slusarz at horde.org]