bug#46979: Allow setting Man-default-entry via Local Variables

[Eli Zaretskii]

> From: 積丹尼 Dan Jacobson <jidanni@jidanni.org>
> Cc: Eli Zaretskii <eliz@gnu.org>,  46979@debbugs.gnu.org
> Date: Mon, 08 Mar 2021 21:46:13 +0800
> 
> So yes, some alists might be possible. But still... there should be a
> way of letting the user use Local Variables per file...

Our solution to this is "C-h S".  Did you try it?  You can extend its
database if the default lacks something you need.