On Mar 20, 2010, at 11:18 PM, John Bowler wrote: > If the GZ data written into the file descriptor is only part of a larger object. I.e. if I want to squirt out some GZ data into the middle of a larger stream. As zlib.h notes, you need to use dup() in that case. close()ing the dup()ed file descriptor does not close the duplicate. Mark