[jcifs] Calling length on open file chokes

[Rob Wygand]

Mike,

Another little oddity, and this was also in 0.5.

If I can length() is a file that is open by another process, I get an 
exception (the file is in use by another process). I see this all the 
time when 'browsing' pagefile.sys. It should be possible to read the 
attrs of a file, even if another process has a write lock on it, no?

I tested this with smbclient, and that returns the right file length...

rjw