Re: Gzip / compression handling? [message #32250] |
Mon, 23 September 2002 16:51 |
Craig Markwardt
Messages: 1869 Registered: November 1996
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Senior Member |
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Doug Rowland <rowland@fields.space.umn.edu> writes:
> I'm using Mac OS X and Solaris. I'm sure what you describe will work, I
> was just hoping for some way that was OS - independent. (At a minimum, I
> would need to be able to do this under Windows. VMS would be a bonus
> but not completely necessary).
>
> Maybe it will boil down to writing separate modules for each platform,
> using your suggestion for unix and unix-like systems.
Hi again Doug--
If you are using Unix, then you might find my seekable pipe library
useful. It will automatically decode compressed files on the fly.
Unfortunately, it insists on writing to a temporary file, so it
doesn't really satisfy one of your original constraints.
Using a straight Unix pipe with "gzcat" is actually a pretty good
option.
Craig
P.S. http://cow.physics.wisc.edu/~craigm/idl/idl.html
--
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Craig B. Markwardt, Ph.D. EMAIL: craigmnet@cow.physics.wisc.edu
Astrophysics, IDL, Finance, Derivatives | Remove "net" for better response
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Re: Gzip / compression handling? [message #32255 is a reply to message #32250] |
Mon, 23 September 2002 15:52  |
Doug Rowland
Messages: 12 Registered: March 2002
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Junior Member |
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I'm using Mac OS X and Solaris. I'm sure what you describe will work, I
was just hoping for some way that was OS - independent. (At a minimum, I
would need to be able to do this under Windows. VMS would be a bonus
but not completely necessary).
Maybe it will boil down to writing separate modules for each platform,
using your suggestion for unix and unix-like systems.
Thanks.
Doug
>
> If you are using a unix system, there might be a way to pipe (|) your
> lun/stream through the gzip/gunzip command. Are you using unix?
>
> -k.
>
>
--
------------------------------------------------------------ -------------------------------
Doug Rowland 472 Tate Laboratory of Physics
Space Physics Laboratory 116 Church Street S.E.
School of Physics and Astronomy Minneapolis, MN
University of Minnesota 55455
work: (612) 624-0378 email: rowland@fields.space.umn.edu
fax: (612) 624-4578
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Re: Gzip / compression handling? [message #32256 is a reply to message #32255] |
Mon, 23 September 2002 15:46  |
Ken Mankoff
Messages: 158 Registered: February 2000
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Senior Member |
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> Date: Mon, 23 Sep 2002 19:53:06 +0000 (UTC)
> From: Doug Rowland <rowland@fields.space.umn.edu>
> Newsgroups: comp.lang.idl-pvwave
> Subject: Gzip / compression handling?
>
> Does anyone know how to handle compressed files in IDL? Is the
> /COMPRESS keyword platform-independent?
I believe its platform independant.
> Maybe more importantly, I want to take a data stream over a network
> that is compressed with gzip, and uncompress it in memory. Any easy
> way of doing this? I would like to avoid writing the stream to disk
> and then reading it back in using the /COMPRESS keyword to OPENR, as
> that might introduce lots of overhead.
If you are using a unix system, there might be a way to pipe (|) your
lun/stream through the gzip/gunzip command. Are you using unix?
-k.
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Re: Gzip / compression handling? [message #32259 is a reply to message #32256] |
Mon, 23 September 2002 13:04  |
Craig Markwardt
Messages: 1869 Registered: November 1996
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Senior Member |
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Doug Rowland <rowland@fields.space.umn.edu> writes:
> Does anyone know how to handle compressed files in IDL?
> Is the /COMPRESS keyword platform-independent?
>
> Maybe more importantly, I want to take a data stream over a network that
> is compressed with gzip, and uncompress it in memory. Any easy way of
> doing this? I would like to avoid writing the stream to disk and then
> reading it back in using the /COMPRESS keyword to OPENR, as that might
> introduce lots of overhead.
Hi Doug--
I've wanted this functionality from IDL too, but I do not believe the
compression routines are available within IDL, nor from the SOCKET
routine.
Yours,
Craig
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