shutil.copyfile is incomplete (truncated)

[Rob Schneider]

> 
> > Or that the filesystem may be full? Of course, that's usually obvious
> 
> > more widely when it happens...
> 
> > 
> 
> > Question: is the size of the incomplete file a round number? (Like
> 
> > a multiple of a decent sized power of 2>)
> 
> 
> 
> Also on what OS X file system type does the file being created reside, 
> 
> in particular, is it a network file system?
> 

File system not full (2/3 of disk is free)

Source (correct one) is 47,970 bytes. Target after copy of 45,056 bytes.  I've tried changing what gets written to change the file size. It is usually this sort of difference.

The file system is Mac OS Extended Journaled (default as out of the box).