On 2021-08-24 16:51:28 +0000, Thorsten Glaser wrote:
> Vincent Lefevre dixit:
>
> >This is incorrect, because SIGINT should be ignored.
> >
> >This issue disappears when the subshell has several commands:
> >
> >$ mksh -c 'trap "" INT; trap; ( :; sleep 3; ); echo $?'
> >trap -- '' INT
> >^C0
>
> Consider this:
>
> $ mksh -c 'trap "" INT; trap; ( :; exec sleep 3; ); echo $?'
> trap -- '' INT
> ^C130
>
> The “one” command run in the subshell is exec’d so you’re hitting
> the parent shell’s INT handler… I think.
>
> Feel free to have a look at the source and see if you come up with
> what exactly seems to be the problem.
This seems to be due to
restoresigs();
in exec.c and the fact that if a subshell contains only one command,
there is an optimization to avoid a fork, as if there were an exec.
Perhaps because of this optimization, the wrong set of signals are
restored?
But I wonder why the signals are restored (and what this does
exactly).
--
Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
