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

[Emeric Jhelil]

Michael M Slusarz a écrit :
> 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
Thanks for the quick reply, but I am not sure that my problem comes from 
an extra space in a config file.
If there is, I have probably not introduced it so I don't know where to 
search.

I have re-tested from scratch :
horde-webmail-1.2.2 (with original dimp-1.1)
drop database ; create database
php horde/scripts/setup.php to generate the basic conf (step 1, 2 and 3)
conf servers.php as minimal as I can (don't see any extra space in string ?)

The result is the same :
if compress_pages = true (it is after using setup.php script), my very 
first log in produces the warnings in apache log but no peculiar 
information in horde.log
if compress_pages = false, no problem
if compress_pages = true and flush is commented out, "no problem"
(compress_pages has been modified by the admin interface)

There is no pb in Imp, just Dimp...

Best regards
Emeric