[Phpmyadmin-devel] "Cannot modify header information" and strange character anomalies.

[Marc Delisle]

Derek Schaefer a écrit :
> On Tue, Jul 14, 2009 at 3:10 PM, Marc Delisle<marc at infomarc.info> wrote:
>> Derek Schaefer a écrit :
>>> Hey all,
>>>
>>> I'm having a couple issues that I can't quite pin down. They aren't
>>> show-stoppers by any stretch of the imagination, but they're still
>>> something I need to work out before the end of the summer.
>>>
>>> I created a notification panel that displays the various structures
>>> created or altered on import. To accomplish this I used the
>>> PMA_Message::notice class to build a string of html, and then
>>> ->display() it, as should be done, I believe. When this panel is
>>> displayed, there are several warnings regarding not being able to
>>> modify header information, header info. already sent, etc. I know what
>>> this means and mostly understand how PHP handles headers, but I'm not
>>> entire sure why it is throwing these errors. Upon a successful import,
>>> there is a PMA_Message::success element displayed under the navigation
>>> buttons that tells how many queries were executed, etc., and that
>>> doesn't cause header problems. I imagine this is cropping up because
>>> of how I am using PMA_Message, although I'm using it in ways
>>> demonstrated elsewhere.
>>>
>>> Also, whenever the aforementioned notification panel is displayed,
>>> strange character anomalies appear at the very bottom of the import
>>> page. They change every time, but always take the form ",�<��Y". My
>>> best guess is that it is related the the header issues, but until I
>>> can get rid of them I can't know for sure.
>>>
>>> Here is a screenshot of the character anomaly and a couple of the
>>> header backtraces:
>>> http://downloads.moonlapse.org/pma/import_issues.jpg
>>>
>>> If anyone has some insight into these issues, I would greatly
>>> appreciate any direction you could give.
>>>
>>> -Derek
>> Are you sure there is not caused by some "echo" debugging statement you
>> left in the code, or some misplaced blank line outside of the PHP tags?
>> Also, if you comment out the calling of PMA_Message, you get rid of the
>> warnings?
> 
> That was my first though, as I had left some around before I had
> created the notification panel and they caused this same problem, but
> I've searched for echo's, print_r's, printf's, etc. etc., and have
> found nothing.
> 
> No extra lines out side PHP tags.
> 
> If I comment out the message section the problem goes away. (The
> message section is in import.lib.php) Even if I just comment out the
> display() call on the message the problem goes away.
> 
>> The strange characters will disappear when your warnings disappear.
>>
>> Finally, does your code in branch/gsoc/derek produce this behavior?
> 
> Yes, it does, as it is an exact replica of my working copy.
> 
>> --
>> Marc Delisle

Tried with your branch on my test machine to replicate the error message 
by clicking on Import (at the server level) and importing a short .sql 
file containing a USE statement and a create table definition. I could 
not see the warnings. Please describe the step-by-step.

Marc

-- 
Marc Delisle
http://infomarc.info