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Date: Mon, 13 May 2013 17:21:17 +0100
From: Peter Stephenson <p.stephenson@samsung.com>
To: Zsh Hackers' List <zsh-workers@zsh.org>
Subject: Re: zpty -r and pipes
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On Mon, 13 May 2013 16:27:20 +0100
Stephane Chazelas <stephane.chazelas@gmail.com> wrote:
> $ zsh -c 'zmodload zsh/zpty; zpty E echo test; zpty -r E'
> test
> 
> But if I pipe it to anything:
> 
> $ zsh -c 'zmodload zsh/zpty; zpty E echo test; zpty -r E | cat'
> $
> 
> No output.
> 
> Those are fine though:
> 
> $ zsh -c 'zmodload zsh/zpty; zpty E echo test; echo $(zpty -r E)'
> test
> $ zsh -c 'zmodload zsh/zpty; zpty E echo test; {zpty -r E} | cat'
> test

First guess and without looking into it is it might be a job control
thing.  Those look just the circumstances where we wouldn't have a
special job in a subshell (pipeline) or where we would (command
substitution, new current-shell process before the fork).

But I could just be wasting typing time.

Not sure what this has got to do with file descriptors anyway.

pws