To show the user an accurate percentage completion, you need to know the  
total amount of work.  There's no way around that.

I don't know what it means to "get the total size of a homeshare" (what's  
a "homeshare"?), but if that involves traversing a directory structure and  
adding up file sizes or something like that, then yes...you can't  
accurately determine the total amount of work without doing the whole  
traversal.  At which point you could have simply finished the work already.

That said, you can do some things to "fake it".  One is to abandon the  
idea of showing progress per se.  Just show some indication of activity so  
that the user knows you're doing _something_.  Another option is to do a  
quick preliminary traversal, enumerating the first one or two directory  
levels, and then base your progress on that.  The relative progress could  
still wind up skewed if there is a huge difference in the work for each  
directory near the top level, but it's about the best you can do in this  
situation.  In most cases, it would provide pretty good feedback to the  
user.

Pete