PetscViewerBinaryOpen getting stuck

[Gideon Simpson]

I have some code that wants to read in a previously binary dumped and  
gzipped matrix.  The first time I run this code, it opens the file  
with PetscViewerBinaryOpen, loads the data into the matrix and  
processes as expected.  However, if, for some reason, I want to  
execute it a second time, when it tries to open the file, it gets  
stuck.  Investigating a bit, it seems to be that the first time it  
runs, when it gunzips the file, it leaves the file in /tmp.  If that  
file is still in this folder, it gets stuck.  If I remove it from / 
tmp, the code executes without a problem, as it did the first time.

Obviously, I could avoid using zipped files.  Is this a bug (or a  
feature)?  Is there an obvious way to clean up /tmp after the code  
executes?

-gideon