Quoting Mark Moseley moseleymark@gmail.com:
I've tried using IMAP with mail_location pointed at the snapshot, but, though I can get a listing of emails in the mailbox, the fetch fails when dovecot can't write-lock dovecot.index.log.
I'm surprised that dovecot would even try to write-lock a write-protected file/directory, though I can appreciate the situation where a file may be in a directory that is writable by some UID other than the one dovecot is running as.
Is there an unsafe control over lock_method similar to Samba's fake oplocks setting in Dovecot?
If anyone wants some good "horror" writing, a perusal of Jeremy Allison's write-up on the schizophrenic approaches to file-locking is worthy of your time.
https://www.samba.org/samba/news/articles/low_point/tale_two_stds_os2.html
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