tcsh being dodgy, or pipe code ishoos?

Juli Mallett jmallett at FreeBSD.org
Tue Jun 24 16:54:11 PDT 2003


* Andrey Chernov <ache at nagual.pp.ru> [ Date: 2003-06-24 ]
	[ w.r.t. Re: tcsh being dodgy, or pipe code ishoos? ]
> On Tue, Jun 24, 2003 at 18:35:15 -0500, Juli Mallett wrote:
> > Anyone with insight into this?
> > 
> > (jmallett at big-lizard:~)39% ( echo 1 ; ( ( echo 2 ; echo 3 ) | xargs -I% echo + % ) )
> > 1
> > + 2
> > + 3
> 
> Loks like stdout/stderr mix, but I not check the code, so just raw guess.

Really?  What makes you say that?  All of these utilities deal with
stdout.  Where does stderr come into it?  Yes I know about TTY races
outputting to stdout and stderr from different processes, especially
how confusing it is to have say

foo | bar | baz

and bar puts something on stderr, and baz buffers for a second.

But I don't see how, practically, this comes into play?  The first is
clearly correct, but throwing a pipe of alll the combined stuff in
seems to complicate matters, so I suspect either buggy pipe code (not
unheard of) or buggy tcsh handling of pipes (possible).

Thanx,
juli.
-- 
juli mallett. email: jmallett at freebsd.org; efnet: juli;


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