php imagepng problems

[Paolo Bonavoglia]

         I send again this message, since I'm not sure it is arrived to the 
list yesterday.
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         A month ago I moved the site of my school from a Win2k server to a 
Linux-Fedora server.

         The site was already hosted by Apache, PhP e MySQL and there was 
no problem in the change.
         Some pages use GD graphics and the imagepng function; imagepng was 
also used by a graphic counter I realized time ago.
         Everything worked fine under Linux Fedora too, but a few days ago 
the graphics crashed suddenly; in the browser (Mozilla or IE just the same) 
you see only the red cross: image error.
(if I call directly the php script, Mozilla says: The image " .... 
file.php?Pagina=6" cannot be displayed because it contains errors.)
         I made some debugging and surely guilty it is the function 
imagepng (or imagejpeg, it's just the same); strangest of all, imagepng 
works perfectly when sending output on a file, e.g.

         imagepng($im, 'figura.png');

but crashes when sending image to the browser (stdout):

         imagepng($im);

         Until now every try to correct the problem failed. Maybe a problem 
of writing rights?

         But why the problem arose suddenly? In the last days I only 
changed some DNS and MySQL configuration, apparently nothing to do with 
graphics.
         I'm not even sure wheter it is a PhP, Apache or Linux problem.

         Any idea?



Regards

Paolo Bonavoglia
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Teacher of mathematics and computer science
Liceo Foscarini [Foscarini High School] - Venice, Italy

Webmaster  http://www.liceofoscarini.it/
E-Mail paolo.bonavoglia at liceofoscarini.it
         paolo_bonavoglia at virgilio.it