I've read several questions here re: uploading a mail collection to an IMAP server or replicating a mail collection and then surfacing it via a local IMAP server.
My situation is slightly different. I would like to place an IMAP server on top of my existing mail collection, not a copy. Said collection is a tree of directories containing
maildir files. It is constantly being updated via
procmail, with files and directories being occasionally created and sometimes even deleted. It's critical that the IMAP server not alter the files or directory structure in any way and not conflict with incoming mail writes.
Is there a mode in Dovecot, Cyrus, your-favorite-imapd, etc. that guarantees that the software will not alter the underlying mail collection in any way? (Obviously I would test the server software on a dummy collection first, but testing can't catch everything.)
This is on Linux.