doveadm import/sync with read-only source location

[Teodor Milkov]

Hello,

Currently doveadm tool can't be used with read-only source locations 
because it's trying to create lock files.

I'd guess lock files shouldn't be necessary on a read-only media, 
because no one else is going to change anything while our doveadm 
instance is running anyway. Example:

doveadm import -u t...@example.com 
maildir:/backup.0/domains/example.com/postmaster/Maildir restored ALL
doveadm(t...@example.com): Error: 
open(/backup.0/domains/example.com/postmaster/Maildir/.Trash/dovecot-uidlist.lock) 
failed: Read-only file system

Perhaps this should be something like doveadm backup -R flag, but in the 
opposite direction – i.e. we have a [full] backup command, but no 
[partial] restore command right now. Or am I missing something?

Best regards,
Teodor