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From: lrg7030@uxa.cso.uiuc.edu (Loren  Rittle)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Pipe syntax... I think I'd better think it out again...
Message-ID: <1990Nov19.031449.25071@ux1.cso.uiuc.edu>
Date: 19 Nov 90 03:14:49 GMT
References: <1990Nov18.090654.24747@agate.berkeley.edu>
Sender: news@ux1.cso.uiuc.edu (News)
Organization: University of Illinois at Urbana
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In message <1990Nov18.090654.24747@agate.berkeley.edu> Pete wrote:

> I got close to it earlier, when I noted that there "aren't many filters
> in AmigaDOS", but I didn't follow the implication.  Heck, there're hardly
> ANY!  How many of the standard command set will process Standard-Input to
> Standard-Output?  Exactly.

While I do agree that many standard commands as shipped from Commodore
(under 1.3 and before) don't ``pipe'' well, all the GNU unix tools do.
All the so called buggy ARP commands that I use everyday with no
problem support reading from standard-in and writing to standard-out.
And every ARexx program I have written that can support piping, does.

> Sure, we can write programs that behave as filters, and there are some unix
> imports that do -- 'compress' filters like a champ, and I suppose grep does
> too (haven't checked) -- but I wonder if that's the best way to do it
> anyway.

> I mentioned (in another article) a simple unix piped command that I'd used:

>             ls -l | grep Nov

<talk about how one might do this under the AmigaOS with standard commands>
<with the conclusion being that unnamed pipes won't work ala unix style.>

I have used that exact command line under the WShell on the Amiga with
GNUgrep v1.5 and LS v4.1ljr.  While these tools were not shipped with
my machine from Commodore, I don't see see it as a problem, as they are
as standard as the Commodore C: commands in my opinion.  Then again my
C: directory is now about 5MB in size, so what I consider standard is
a bit more than some (most perhaps) others.  If the standard tools
don't pipe they should be fixed, and may very well already be fixed in 2.0.
I just think it is important to note that un-named piping does work
under the AmigaOS if the programs are written to be used as filters.
And as I state above, many have been designed with filtering in mind.

What am I saying here, you might wonder?  I like piping to work the
way it currently works on my system.  This is not to say that you
should not continue work on the PIPE command it does sound neat, but
the statement that AmigaOS does not support unnamed pipes is false.
I think the PIPE command with it's ability to fork output and input
to multiple people would be quite useful, an extension to what I
currently have, but the new ability to add something like unnamed
piping to commands that don't support it sounds like a kludge.
By the way, many commands that won't handle piping won't handle
any better under your new idea. The MORE command as distributed
by Commodore is a prime example:

MORE <PIPE:AA
and 
MORE PIPE:AA

using any pipe device you care to use causes the MORE command to
get quite upset, at least under the 1.3 version of MORE.
The command seems to have a problem with files that it can't seek
on. (PS Bill Hawes version of MORE has a similar problem when
working with pipes, at least the latest version I have does.)
LESS, another non-standard standard command is the only pager
that I have found that supports pipeing the way it should.

There I have said my peace, go for the PIPE command (like RUN) as
you were talking about, but this last change you talked about
sounds like it is of questionable value.
Loren J. Rittle