imap-message-copy
imap-message-copy is a compiled Lisp function in `imap.el
'.
(imap-message-copy ARTICLES MAILBOX &optional DONT-CREATE NO-COPYUID BUFFER)
Copy ARTICLES to MAILBOX on server in BUFFER.
ARTICLES is a string message set. Create mailbox if it doesn't exist,
unless DONT-CREATE is non-nil. On success, return a list with
the UIDVALIDITY of the mailbox the article(s) was copied to as the
first element. The rest of list contains the saved articles' UIDs.