Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!leah!wfh58
From: wfh58@leah.Albany.Edu (William F. Hammond)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Pipes
Summary: "|" has two peacefully co-existing meanings in the ARP shell
Message-ID: <3149@leah.Albany.Edu>
Date: 9 Jun 90 21:48:11 GMT
References: <2533@zipeecs.umich.edu> <136735@sun.Eng.Sun.COM> <1990Jun6.104643.15176@zorch.SF-Bay.ORG> <12373@cbmvax.commodore.com>
Reply-To: wfh58@leah.albany.edu.UUCP (William F. Hammond)
Organization: Dept of Math & Stat, SUNYA, Albany, NY
Lines: 51

In article <12373@cbmvax.commodore.com> jesup@cbmvax (Randell Jesup) writes:
. . .
>	The #? comes from Tripos, back from the early '80's in England.
>It's historical, not "not invented here".  2.0 has far more capable wildcards,
>with classes, ~(not), etc.  Even * if you set a flag in the system, though not
>by default so we don't break existing scripts and apps.

I'm very glad to hear that "*" as a wild card is a configuration option under
OS 2.  I hope this also means that an alternate escape character will also
be a configuration option.

>	As for pipes, there are any number of third party shells that have
>the '|' syntax, just as in Unix there are any number of alternate shells that
>have better editing than csh or sh.  Once again, turning '|' into a piping
>character would break existing scripts and applications.

I have both WShell (commercial) and the ARP 1.3 Shell (freeware).
I hope everyone knows that there is a freeware product which supports
the concurrent piping (with the "|" symbol) that is part of the "ConMan"
console handler.  (In fact, I tend to prefer the ARP shell because it
has command line substitution.  Against WShell, it has the distinct
disadvantage of not opening an ARexx port.)

I have never had trouble in the ARP shell with the two meanings of "|"
(i.e., as (1) pipe and (2) first string OR second string) probably because
the "OR" syntax always occurs inside parentheses while the pipe syntax does
not.  Maybe this is just the idiosyncrasy of my usage.

>	2.0 also has improved support for "user shells", so programs can
>submit things generated by the user to his/her preferred interactive shell,
>while continuing to send program-generated command lines through the
>normal shell (so things like syntax differences won't break them).

This also sounds very good.

By the way, although "pip:"-style concurrent piping is extremely useful
(I daily use pipes of length 4), there are times when "pipe:"-style
rendezvous pipes are what I want.  After all, there is only one stdout stream
and sometimes I want several outgoing streams.  So PLEASE PLEASE do not throw
out "PIPE:".  We want both kinds of piping available.

>-- 
>Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
>{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com  BIX: rjesup  
>Common phrase heard at Amiga Devcon '89: "It's in there!"

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William F. Hammond                   Dept. of Mathematics & Statistics
518-442-4625                         SUNYA, Albany, NY 12222
wfh58@leah.albany.edu                wfh58@albnyvms.bitnet
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