Re: wait and SIGSTOP

[Hadrien Lacour <hadrien.lacour@xxxxxxxxxx>]

On Mon, Nov 12, 2018 at 05:08:15PM +0100, Hadrien Lacour wrote:
> Hello,
>
> after reading https://www.mail-archive.com/dash@xxxxxxxxxxxxxxx/msg00683.html,
> I still wonder what the correct behaviour is supposed to be. The last message
> lets me think that untrapped signals shouldn't interrupt wait. With the script
>
>     #!/bin/dash
>
>     sleep 100 &
>     echo $!
>     wait $!
>     echo status: $?
>
> wait still exits immediatly with status 128 when I kill -STOP the output pid
> . The other shells I tested still wait for the job and give me:
> * bash: 143
> * zsh: 147
> * busybox ash: 143
>
> (this was using dash 0.5.10.2)
>
>
> Sincerly,
> Hadrien Lacour

After some more testing, I'm even more confused, here's what I get when
1) running kill -STOP then kill -CONT on sleep
2) running kill on sleep

+-------------+-------------------------------+------+
| shell       | kill -STOP; kill -CONT        | kill |
+-------------+-------------------------------+------+
| zsh         | 147                           | 143  |
+-------------+-------------------------------+------+
| bash        | 0                             | 143  |
+-------------+-------------------------------+------+
| busybox ash | 0                             | 143  |
+-------------+-------------------------------+------+
| dash        | 128 (SIGSTOP interrupts wait) | 143  |
+-------------+-------------------------------+------+

After reading `man 1p wait` more carefully, I think that bash and busybox ash
have the correct behviour.