[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: SIGINT handling
From: |
Stephane Chazelas |
Subject: |
Re: SIGINT handling |
Date: |
Mon, 21 Sep 2015 10:48:07 +0100 |
User-agent: |
Mutt/1.5.21 (2010-09-15) |
2015-09-19 21:36:28 +0100, Stephane Chazelas:
> 2015-09-18 16:14:39 +0100, Stephane Chazelas:
> [...]
> > In:
> >
> > bash -c 'sh -c "trap exit INT; sleep 10; :"; echo hi'
> >
> > If I press Ctrl-C, I still see "hi".
> [...]
>
> Jilles provided with the explanation at
> http://unix.stackexchange.com/a/230731
>
> with a link to:
> http://www.cons.org/cracauer/sigint.html
[...]
Note that bash (and ksh, contrary to FreeBSD sh) is not
consistent in its handling of that "WCE" (for "wait and
cooperative exit") approach in that pressing ^C in:
bash -c '
var=$(sh -c "trap \"\" INT; sleep 3; echo result)
echo "$var"
'
kills bash, leaving the "sh" and "sleep" running unattended in
background.
Same for:
bash -O lastpipe -c '
sh -c "trap \"\" INT; sleep 3; echo test" | read var; echo done'
One could also argue, that to be consistent, SIGTSTP and SIGQUIT
should be treated similarly (strangely enough
http://www.cons.org/cracauer/sigint.html doesn't mention SIGTSTP).
I'm not sure I prefer that WCE approach over WUE. Wouldn't it be
preferable that applications that intercept SIGINT/QUIT/TSTP for
anything other than clean-up before exit/suspend implement job
control themselves instead (like vi's :! should create a process
group and make that the foreground process group of the
terminal so pressing ^C in sh -c vi, :!sleep 10, only sends the
SIGINT to sleep)?
--
Stephane
- SIGINT handling, Stephane Chazelas, 2015/09/18
- Re: SIGINT handling, Stephane Chazelas, 2015/09/19
- Re: SIGINT handling,
Stephane Chazelas <=
- Re: SIGINT handling, Chet Ramey, 2015/09/21
- Re: SIGINT handling, Stephane Chazelas, 2015/09/21
- Re: SIGINT handling, Stephane Chazelas, 2015/09/21
- Re: SIGINT handling, Chet Ramey, 2015/09/22
- Re: SIGINT handling, Stephane Chazelas, 2015/09/22
- Re: SIGINT handling, Stephane Chazelas, 2015/09/22
- Re: SIGINT handling, Stephane Chazelas, 2015/09/22