need some documentation on folderfilter and nametrans

[Payal]

Hi all,
I would appreciate some docs on folderfilter and nametrans. Some
examples will also help. I couldn't understand much from the official
readme file.
I have 2 machines - A and B. I want to sync mails currently in A's
Maildir/ into B's Maildir/old-mails/ and not in INBOX.

Can someone help please? Also, what does "realdelete" do?

With warm regards,
-Payal
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