bug#63311: 30.0.50; [PATCH] smtpmail-send-it split

[Eli Zaretskii]

> Date: Fri, 05 May 2023 15:13:32 +0200
> From:  Manuel Giraud via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> BTW, does anyone know the purpose of 'errbuf': I see it is created then
> erased and then killed?

Looks like a left-over from when this function was written.  It is
basically a rewrite of sendmail-send-it, which does use that variable.