Re: does zsh ignore the QUIT signal?

[Peter Stephenson <p.w.stephenson@xxxxxxxxxxxx>]

Vincent Lefevre wrote:
> When I type "while true; do true; done" from an interactive zsh shell,
> I can't interrupt it with SIGQUIT (either with Ctrl-\ or with the
> "kill -QUIT <pid>" command): sending this signal has no effect. Is
> this normal?

Yes, although I had to search the source code to find this out.  The
shell has ignored it at least as far back as the CVS archive goes (April
1999).

This should let you interrupt the shell with it:
  TRAPQUIT() { return $(( 128 + $1 )); }
It doesn't set the return status, unlike SIGINT, however (and because
it's handled there's no core dump).

This documents it.

Index: Doc/Zsh/jobs.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/jobs.yo,v
retrieving revision 1.4
diff -u -r1.4 jobs.yo
--- Doc/Zsh/jobs.yo	2 Jul 2004 14:59:14 -0000	1.4
+++ Doc/Zsh/jobs.yo	29 Mar 2006 19:04:07 -0000
@@ -95,6 +95,7 @@
 The tt(INT) and tt(QUIT) signals for an invoked
 command are ignored if the command is followed by
 `tt(&)' and the tt(MONITOR) option is not active.
+The shell itself always ignores the tt(QUIT) signal.
 Otherwise, signals have the values
 inherited by the shell from its parent
 (but see the tt(TRAP)var(NAL) special functions in noderef(Functions)).

-- 
Peter Stephenson <p.w.stephenson@xxxxxxxxxxxx>
Web page still at http://www.pwstephenson.fsnet.co.uk/