Yes now the console stay frozen 40 sec. .... and before I see turn [-\|/-] .. chars
Well, it is a pretty big file... But still, is faster than you said it was before... I am not sure if you can make it load faster. Probably this is the best solution, because if you were to load it in an intermediate buffer, you would still loose some time with the loading part. Then, the QDomDocument would still have to parse your buffer, so you're back at square one...

To provide feedback to the user while loading large files, you could do the loading in a separate thread ( or use a QTimer and notify the user every 5 secs, let's say, that the file is still loading ). of course, this depends on how much need the user has to be notified .

Have you find a class to display Postcript file? or PDF? .. I put XPDF Libs on ice to Window...
No, unfortunately. I still plan to modify xpdf on my own and integrate it with qt, but this as soon as I find some spare time ( a lot of free time ).
I don't know of any other pdf library as complete as xpdf out there ( well, except the Adobe pdf Library ).

Regards