> I would like to detect the situation where a file
> needs to be updated. If that is the case, I would like
> to not overwrite that file, instead I would rename the file
> using a suffix like "<original_nam>_newFile".

Humm, this is not an easy task for html data, because httrack always modify
them (as internal links might have to be updated to apply modified options, or
structural changes)

You can't neither use the "receive-header" callback, as the filename is not
always known at this stage.

I'll probably have to create a "store-link" callback of something similar,
called each time a link location is being created (added on the TODO list)

In the meantime, a copy of the project, and a recursive diff after the mirror,
might fit your needs ?
> PS: I'm spaniard...what doest it mean "lien_back" ? :P

Humm, some bad frenglish name :p