gnus: Article Marks
6.4.13.9 Article marks
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An article identified by ‘uniq’ is considered to have the mark ‘flag’
when the file ‘.nnmaildir/marks/flag/uniq’ exists. When Gnus asks
‘nnmaildir’ for a group’s marks, ‘nnmaildir’ looks for such files and
reports the set of marks it finds. When Gnus asks ‘nnmaildir’ to store
a new set of marks, ‘nnmaildir’ creates and deletes the corresponding
files as needed. (Actually, rather than create a new file for each
mark, it just creates hard links to ‘.nnmaildir/markfile’, to save
inodes.)
You can invent new marks by creating a new directory in
‘.nnmaildir/marks/’. You can tar up a maildir and remove it from your
server, untar it later, and keep your marks. You can add and remove
marks yourself by creating and deleting mark files. If you do this
while Gnus is running and your ‘nnmaildir’ server is open, it’s best to
exit all summary buffers for ‘nnmaildir’ groups and type ‘s’ in the
group buffer first, and to type ‘g’ or ‘M-g’ in the group buffer
afterwards. Otherwise, Gnus might not pick up the changes, and might
undo them.