Re: `jobs` shows output even when nothing has been started in the background

[Chet Ramey]

On 6/14/23 4:47 AM, Ajeet D'Souza wrote:

> Bash Version: 5.2
> Patch Level: 15
> Release Status: release
>
> *Description:*
> I apologize if this is not a bug, but I couldn't find any documentation
> around this behaviour.
>
> In Bash, this does not produce any output:
> /bin/echo; jobs -l
>
> But if you run it in a subshell, it does:
> (/bin/echo; jobs -l) # output: [1]  42135 Done                    /bin/echo
>
> Similar problem if you put this into $PROMPT_COMMAND, although it does not
> run in a subshell AFAIK:
> PROMPT_COMMAND='/bin/echo; jobs -l' # output on every prompt: [1]  42135
> Done                    /bin/echo
>
> This happens only for external processes, if you were to use the builtin
> echo, it would not show any background process. 

Thanks for the report. I changed this back in late September, 2022 after
a bug-bash discussion:

https://lists.gnu.org/archive/html/bug-bash/2022-09/msg00067.html

The original report was

https://lists.gnu.org/archive/html/bug-bash/2022-07/msg00117.html

The original (through bash-5.2) behavior was due to the subshell not
notifying the user about the status of the completed foreground job,
even though not running it in a subshell ignored foreground jobs. The
fix was to remove terminated foreground jobs the shell would never notify
the user about (foreground jobs not killed by a signal) from the jobs list.

Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/