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I have not had a chance to look at the data yet, but I think Bob's observation may be the key. ZLIB always refers to the compression scheme used by gzip (because gzip uses zlib). On Mon, 6 Nov 2000, NIMBUS Librarian wrote: > > Folks, > > Don't forget that you need to account for the WMO header > at the front of the data... it's not compressed, so it'll > need to be stripped out first. > > Bob Lipschutz > FSL > > > > > > In a previous message to me, you wrote: > > > > > > > >Pete... > > > > > >You are trying to make things too complicated. Most data compression > > progr > ams > > >have some easy of way of sending uncompressed data to stdout. The ones > > tha > t > > >I know about are: > > > > > > Scheme Command to use > > > pack pcat > > > compress zcat > > > gzip (ZLIB) gzcat or zcat (depending on how it was built) > > > bzip2 bzcat > > > > > >The only one that I can't find a way, (at least via the man pages that I > > ha > ve) > > >is "zip". > > > > > >As a sample: > > > > > > cat file.gz | gzcat > > > > > >would get you the ungzipped version of "file". > > > > Hi Kevin, > > > > That's not exactly the problem here. The NEXRAD files are not > > zip'd files, they just happen to use one of the same compression > > algorithms that zip does. They are not in 'zip' format, so > > the stdio version (funzip on unix) doesn't recognize them. > > > > > > > >By the way, if you really want to program via ZLIB, just use "gzopen" and > > >"gzread". It is easy to do using these calls. > > > > That would work if the files were in gzip format, but they aren't, > zlib used to use gzip format but apparently it now uses the > > deflate/inflate algorithms, so I don't think gzopen and > > gzread will do it... > > > > There are other routines in the zlib library to inflate > > deflated data, it's just a matter of writing the program > > to call them. > > > > Am I way off base here? > > > > Pete > > > > > > > > > > Kevin W. Thomas > > > Sun System Administrator & Meteorologist > > > National Severe Storms Laboratory > > > Norman, Oklahoma > > > > > > Email: address@hidden > > > > > > -- > > +>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+ > > ^ Pete Pokrandt V 1447 AOSS Bldg 1225 W Dayton St^ > > ^ Systems Programmer V Madison, WI 53706 ^ > > ^ V address@hidden ^ > > ^ Dept of Atmos & Oceanic Sciences V (608) 262-3086 (Phone/voicemail) ^ > > ^ University of Wisconsin-Madison V 262-0166 (Fax) ^ > > <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+ > -------------------------------------------------------- David Wojtowicz, Sr. Research Programmer/Systems Manager Department of Atmospheric Sciences Computer Services University of Illinois at Urbana-Champaign email: address@hidden phone: (217)333-8390 --------------------------------------------------------