bug#37564: [PATCH] don't export LINES and COLUMNS env vars in term to fix ncurses applications

[Lars Ingebrigtsen]

Eli Zaretskii <eliz@gnu.org> writes:

>> PS for an example of the effect, one can use some of the programs in
>> the ncurses-examples from
>> https://invisible-island.net/ncurses/ncurses-examples.html
>> 
>> eg "worm".
>
> I understand that applications based on ncurses are affected, but what
> about those which aren't based on ncurses?

I think the rough consensus here was that adding LINES/COLUMNS is
usually the wrong thing to do, but Eli worries that this might break
something.  So I've applied Matthew's patch, but also added a defcustom
to control this.

I've defaulted the variable to "don't add the variables", but if this
leads to problems during the Emacs 28.1 cycle, we can flip it to "on"
later.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no