Process/Prefix
==============

   Many functions, among them functions for moving, decoding and saving
articles, use what is known as the "Process/Prefix convention".

   This is a method for figuring out what articles that the user wants
the command to be performed on.

   It goes like this:

   If the numeric prefix is N, perform the operation on the next N
articles, starting with the current one.  If the numeric prefix is
negative, perform the operation on the previous N articles, starting
with the current one.

   If `transient-mark-mode' in non-`nil' and the region is active, all
articles in the region will be worked upon.

   If there is no numeric prefix, but some articles are marked with the
process mark, perform the operation on the articles that are marked with
the process mark.

   If there is neither a numeric prefix nor any articles marked with the
process mark, just perform the operation on the current article.

   Quite simple, really, but it needs to be made clear so that surprises
are avoided.

   One thing that seems to shock & horrify lots of people is that, for
instance, `3 d' does exactly the same as `d' `d' `d'.  Since each `d'
(which marks the current article as read) by default goes to the next
unread article after marking, this means that `3 d' will mark the next
three unread articles as read, no matter what the summary buffer looks
like.  Set `gnus-summary-goto-unread' to `nil' for a more
straightforward action.