progress bar use

[Nick Belshaw <nick s belshaw googlemail com>]

HI - hope this is the best mailing list...

I would like to implement a progress-bar to make clear to users stuff is
happening.
Specifics involve loading and pre-processing of files. Some files might be
very big requiring some 10's of seconds to do all stuff.
At the moment the processing of the files blocks any updates I try to push
to the progress bar.
Do I have to go to threads or is there another way of handling this?

grateful for any comments

regards

Nick