Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.tech
Subject: Re: PIPEs
Keywords: PIPE, IP-Device
Message-ID: <15681@cbmvax.commodore.com>
Date: 7 Nov 90 19:04:29 GMT
References: <1990Oct19.044319.4851@engin.umich.edu> <1990Nov2.091542.25505@agate.berkeley.edu> <1990Nov2.173103.18889@engin.umich.edu>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Distribution: na
Organization: Commodore, West Chester, PA
Lines: 28

In article <1990Nov2.173103.18889@engin.umich.edu> gilgalad@caen.engin.umich.edu (Ralph Seguin) writes:
>In article <1990Nov2.091542.25505@agate.berkeley.edu> pete@violet.berkeley.edu (Pete Goodeve) writes:

>The major problem with any of the pipe implementations for the Amiga is
>that they build "named" temporary files.  Kinda bad, when you're trying
>to use pipes as an IPC with files larger than a megabyte.  For instance:

>ilbmtoppm blah.iff|ppmquant 256|ppmscale -yscale 1.4|ppmtogif >blah.gif

>Hmmm... Let's see, that's 3 megs worth of temp files.

Say what?  Looks more like 12K-24K of temp storage to me, if you're using one
of the more common type of named pipe devices that sports a 4K buffer between 
input and output streams.  While a pipe should really be based on a FIFO rather 
than a buffer (so you can start reading it as soon as it's created, or at
least as soon as the first block is written to it, rather than waiting on the 
buffer to fill) there's no reason at all why any Amiga pipe device should act 
like MS-DOS fake pipes and use temporary files.  A named pipe is hardly a
temporary file.  Do you really know of any Amiga pipe device/handlers that
wimp out and actually require the whole file to be buffered?

>			See ya, Ralph


-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
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	Standing on the shoulders of giants leaves me cold	-REM