From: Mikael Magnusson <mikachu@gmail.com>
To: Daniel Shahaf <d.s@daniel.shahaf.name>
Cc: Ben Klein <robobenklein@gmail.com>, Zsh Users <zsh-users@zsh.org>
Subject: Re: Capturing STDOUT without subshells or file I/O
Date: Mon, 17 Sep 2018 23:01:40 +0200 [thread overview]
Message-ID: <CAHYJk3QeRVJkHXcyFcPMKKNQg1A+3qM=1mbXqJTbrjVuE617vA@mail.gmail.com> (raw)
In-Reply-To: <1537217203.28092.1511309952.71C4C11C@webmail.messagingengine.com>
On Mon, Sep 17, 2018 at 10:46 PM, Daniel Shahaf <d.s@daniel.shahaf.name> wrote:
> Ben Klein wrote on Mon, 17 Sep 2018 16:13 -0400:
>> So I guess the question is up again, how should I capture the `printf`
>> output without the `-v` option, no subshells, and no file I/O? Is there
>> a different method for ZSH v5.1?
>>
>> I would like to do `printf '%.2f' "3.4" | read var` but it appears that
>> the command before the pipe causes a subshell to be opened.
>>
>
> If you could call pipe(2), you'd be able to do
> .
> printf foo >&$w
> read bar <&$r
> .
> without forking (where $r,$w were returned by pipe(2)). However, I
> don't see any suitable callsite in the 5.6 codebase. (Don't have 5.1
> handy, sorry.)
>
> Maybe we should expose pipe(2) in zsh/system?
That's just a deadlock-by-design.
--
Mikael Magnusson
next prev parent reply other threads:[~2018-09-17 21:01 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-02 20:57 Ben Klein
2018-09-03 0:40 ` Joey Pabalinas
2018-09-03 14:02 ` Daniel Shahaf
2018-09-03 18:43 ` Joey Pabalinas
2018-09-17 20:13 ` Ben Klein
2018-09-17 20:46 ` Daniel Shahaf
2018-09-17 21:01 ` Mikael Magnusson [this message]
2018-09-17 21:20 ` Bart Schaefer
2018-09-17 21:19 ` dana
2018-09-17 21:33 ` Bart Schaefer
2018-09-18 5:12 ` Sebastian Gniazdowski
2018-09-21 6:58 ` Oliver Kiddle
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