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Marking Groups
==============

   If you want to perform some command on several groups, and they
appear subsequently in the group buffer, you would normally just give a
numerical prefix to the command.  Most group commands will then do your
bidding on those groups.

   However, if the groups are not in sequential order, you can still
perform a command on several groups.  You simply mark the groups first
with the process mark and then execute the command.

`#'
`M m'
     Set the mark on the current group (`gnus-group-mark-group').

`M-#'
`M u'
     Remove the mark from the current group (`gnus-group-unmark-group').

`M U'
     Remove the mark from all groups (`gnus-group-unmark-all-groups').

`M w'
     Mark all groups between point and mark (`gnus-group-mark-region').

`M b'
     Mark all groups in the buffer (`gnus-group-mark-buffer').

`M r'
     Mark all groups that match some regular expression
     (`gnus-group-mark-regexp').

   Also see Process/Prefix..

   If you want to execute some command on all groups that have been
marked with the process mark, you can use the `M-&'
(`gnus-group-universal-argument') command.  It will prompt you for the
command to be executed.