ZLib and GZip and memory-buffered operation

Hello all,

I'm currently getting started with the GZip part of ZLib. I've dealt
with the usual ZLib stuff (on a rather surfacial manner) previously,
but I'm new to the GZip routines.
They look pretty straight forward to me so far, but I have a question.
In order to do what I want to do, I need a routine that allows me to
do in-memory-expansion of a file rather than a file-to-file expansion.
Reason is, that my sources are not available as a file, but as a
memory-buffer.
course, I could dump my buffer to a temporary file and use the
normal routines (gzopen, gzread, gzclose) with that, but that seems to
be like scratching your ears with your toes rather than with your
hands. Somewhat.

How can I decompress a GZ-zipped buffer (that once was a file, but not
on my system) with the standard ZLib library functions without using
the file-oriented i/o?

Thanks for any hints!
Regards,
Pelle.