konsole showing output from unidentified background processes and syslogs?

[René J.V. Bertin]

On Sunday May 13 2018 06:07:16 Duncan wrote:

Hi,


>There's the notion of a "system console" that gets various higher 
>priority kernel log messages, and a similar "console log" setting for 
>most syslog daemons including systemd's journald.  These are normally 
>routed to a text terminal, termed the "system conosle", but they can be 

Yes, I remember there used to be (= I used to use) such a thing, but IIRC that went through /dev/console. On the current system, that device is +rw for root only, and output sent there doesn't show up on the "infected" pseudo-terminal.

>never been enough to actually go researching further myself (I just 
>grumble and hit refresh if need be), so if you happen to find a helpful 
>article on the topic, please post a link.  That might be the perfect 
>"round tuit" that I never seem to get, otherwise. =:^)

I just realised that this will help:

%> sudo ll /proc/*/fd/* | fgrep /pts/2

That showed kdeinit5 (and its klauncher child) as the source of the KF5-related message:
3697254 lrwx------ 1 bertin bertin 64 May  7 16:09 /proc/28256/fd/1 -> /dev/pts/2
3697255 lrwx------ 1 bertin bertin 64 May  7 16:09 /proc/28256/fd/2 -> /dev/pts/2
3697277 lrwx------ 1 bertin bertin 64 May  7 16:09 /proc/28257/fd/1 -> /dev/pts/2
3697278 lrwx------ 1 bertin bertin 64 May  7 16:09 /proc/28257/fd/2 -> /dev/pts/2

I cannot remember restarting kdeinit5 by hand from that termial. Is it possible that these /dev/pts devices get reused, i.e. that a Konsole tab finds itself using a pseudo-terminal devicec that's already being used as stdout/stderr by another process?

Cheers,
R.