Re: Ctrl-\ while executing a pipeline made zsh quit

[Vincent Lefevre <vincent@vinc17.net>]

On 2022-04-25 18:24:15 -0700, Bart Schaefer wrote:
> On Mon, Apr 25, 2022 at 5:37 PM Vincent Lefevre <vincent@vinc17.net> wrote:
> >
> > With zsh 5.8.1 under Linux (zsh 5.8.1-1 Debian/unstable package),
> > while I was executing a pipeline, I typed Ctrl-\ to interrupt it
> > (Ctrl-C had no effect), which made unexpectedly zsh quit: SIGQUIT
> > should interrupt the commands zsh starts, not the interactive shell
> > itself.
> 
> I'm unable to reproduce this on Ubuntu 20.04 with 5.8.1.2-test.

I can't reproduce it either. This may be a timing related issue:
perhaps there's some place where if a signal is received, everything
goes wrong (Ctrl-C normally has an effect, so perhaps things were
wrong when I first try Ctrl-C).

The only case I had found where Ctrl-C had no effect was this bug:

  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=931216
  https://github.com/gwsw/less/issues/12

i.e. in case of process substitution, but here there was no such thing.

Or perhaps the cause of the issue was that here, the Ctrl-C didn't
kill the left-hand side (possibly because the ssh started by svn
got frozen... not sure).

> I vaguely recall there's actually a bug in some version(s?) of "less"
> that causes its parent to exit?

I'm not aware of that, and I don't see how this could be the fault
of "less" (unless it kills his parent, but why would it do this?).

> I did discover that if "less" exits with an error, the whole pipeline
> becomes unkillable with either INT or QUIT; the shell is hung until
> the left side exits.

If "less" really exits, how could this happen?

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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