Re: Prevent B c/B m from createing dups in target group

[Harry Putnam <reader@newsguy.com>]

Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Großjohann) writes:

> I wonder if one of the variables help that are about duplicates in
> Gnus?
> 
> M-x apropos-variable RET gnus.*dup RET
> 

Yeah, I knew about those but the first relies on splitting or
respooling which is not activated in B c or B m usage.

And it seems that at least one of the others depends on that `Warning'
thing being present.  Even if the middle one (below) checks message
IDs it still only hides there presence by my reading.  So that other
ways of accessing that directory would still find them.

Further, none of it has any provision for notifying the user that they
are dealing with dups and allowing a choice of proceeding or not.
( That is, other than the 'Warning' header in the case of split stuff )

With that warning mechanism in place, and provision to copy/move only
the unique messages on command, a user could simply throw a batch of
messages at a directory and only the unique stuff would stick...

========================================

gnus-duplicate-mark
  Variable: *Mark used for duplicate articles.
gnus-summary-ignore-duplicates
  Variable: *If non-nil, ignore articles with identical Message-ID headers.
gnus-suppress-duplicates
  Variable: *If non-nil, Gnus will mark duplicate copies of the same article as read.