Re: background process not inheriting pts device

[Luuk van Baal]

> > Thanks for your detailed response, my bad for missing the relevant release
> > note.
> 
> It's not obvious from reading it (I have the advantage of remembering why
> I did these changes).
>  
> > tty returns "not a tty" inside the script so while your assumption is 
> > correct, 
> > your suggested solution unfortunately does not help me.
> > 
> > Sending the function where tty is called to the background
> > 
> >     foo & # where foo is a shell script function name
> > 
> > , makes tty return "not a tty". I think this is expected behavior and the 
> > same
> > behavior was present in ncurses 6.2.
> > 
> > But the fact remains that in 6.2 the pts device was inherited by sub-shells 
> > whereas
> 
> I'm puzzled why your trace shows file descriptors 0 and 1 open on /dev/pty/10,
> but opening 11 on /dev/pts/10 (if the first two aren't a tty, then the last
> wouldn't be).
> 
> > in 6.3 this is no longer the case. If this is intended I guess I will 
> > resort to
> > manually passing the pts device of the main shell:
> > 
> >     TTY="$(tty)"
> >             TTY="$TTY" foo &
> 
> yes... I don't see a way to improve this (reverting that change would
> get different bug-reports).  But there's that unexplained detail, so
> I added a to-do item to investigate further.
> 
> -- 
> Thomas E. Dickey <dickey@invisible-island.net>
> https://invisible-island.net
> ftp://ftp.invisible-island.net

The script redirects stderr to /dev/null (to not bother users with error 
messages
regarding preview generation, it's a preview script for the file manager).
I noticed when removing error redirection, the missing pts device for the 
sub-shell
IS created and tput reports the correct terminal dimensions on ncurses 6.3.

Perhaps this can help you track something down but bear in mind that it is 
probably
a very niche use-case with the preview script being spawned by the file-manager
and the preview-script itself running inside a tmux/kitty/external terminal 
instance.
I won't bother you with it further as the workaround is satisfactory for me.

Thanks again,
Luuk van Baal <luukvbaal@gmail.com>