Re: gplt_x11 ignores SIGINT and SIGTSTP. Why?

[Dima K. <gn...@di...>]

Hans-Bernhard Bröker <HBB...@t-...> writes:

> Am 02.09.2022 um 02:22 schrieb Dima Kogan:
>
>> It feels like an odd thing to do to specifically mask out SIGTSTP,
>> but I guess that's fine. Masking out SIGINT creates zombies, though,
>
> Well, the documented intent is to keep gnuplot_x11 from being killed
> by Ctrl-C or Ctrl-Z typed into the console --- presumably the one its
> parent gnuplot process was started from.

But you DO want it to die when the user hits C-c on the console!
Otherwise you get zombies. There's some logic in there to die via a more
"controlled" path or something, so most of the time the child
gnuplot_x11 process does go away in response to a C-c, but sometimes it
doesn't. I do see straggler gnuplot_x11 processes sometimes. And when
debugging some updates to gnuplot_x11 I see them all the time.


> It would be _very_ surprising to find out that this particular snippet
> would have been as badly wrong as you claim it to be, after all this
> time. X11 may be considered unimportant by some today, but that
> definitely would have been no excuse of the majority of that time
> frame.

I claim there's a bug, not that gnuplot_x11 is horribly, unusably
broken. There are other gnuplot_x11 bugs that definitely exist that I
can report too, but nobody has the cycles to work on them (including
me), so that's not obviously useful.