bug#24518: 25.2.50; dired-mark-extension with prefix arg fails

[Eli Zaretskii]

> From: Andreas Schwab <schwab@linux-m68k.org>
> Cc: Tino Calancha <tino.calancha@gmail.com>,  24518@debbugs.gnu.org
> Date: Sat, 24 Sep 2016 15:15:01 +0200
> 
> Does it actually make sense to have to specify the character by its
> code?

Like I said: it looks a kludge, but it definitely isn't an accident.
I suggested to replace 'P' with 'c' in the interactive spec, to make
it less kludgey.

> That doesn't look like this was an intented feature (being
> undocumented).

It's documented, see the doc string.