mail_location setting has started becoming a bit bloaty. I'm not actually even sure why I've kept adding more parameters to it rather than just adding new settings. It's also caused confusion, because people try things like:

mail_location = mbox:/var/mail/%u mail_location = mbox:INBOX=/var/mail/%u

Although the first one has been giving ok enough error message for a long time now and the second one also will give in v2.0.10, it still would be nicer if there wasn't any need for such confusion at all. The settings could instead be:

mail_format = mbox mail_inbox_path = /var/mail/%u

Then Dovecot could complain about mail_root_path being empty, which would be more understandable..

The mail_location setting itself would keep working probably forever for backwards compatibility (and also in some setups it would be difficult to split it when it comes from LDAP/SQL), although some of its parameters could maybe be dropped after a while (SUBSCRIPTIONS, DIRNAME, MAILBOXDIR). So if you did e.g.:

mail_location = mbox:~/mail:INBOX=/var/mail/%u mail_root_path = ~/mail2

The result would be same as mbox:~/mail2:INBOX=/var/mail/%u. Although this can also result in probably unwanted situation:

mail_location = mbox:~/mail:INBOX=/var/mail/%u mail_format = maildir mail_root_path = ~/Maildir

Now the result would be maildir:~/Maildir:INBOX=/var/mail/%u. This can be avoided by setting mail_inbox_path="" explicitly. Or the other way around:

mail_inbox_path = /var/mail/%u mail_location = maildir:~/Maildir:INBOX=

Without the INBOX= the mail_inbox_path would be in use.

Below are the setting names I thought about using:

a) mail_location = maildir:~/Maildir:INBOX=~/Maildir/.INBOX:INDEX=~/indexes:CONTROL=~/control:LAYOUT=fs:SUBSCRIPTIONS=courier-subscriptions

mail_format = maildir mail_root_path = ~/Maildir mail_inbox_path = ~/Maildir/.INBOX mail_index_path = ~/indexes mail_control_path = ~/control mail_directory_layout = fs mail_subscriptions_fname = courier-subscriptions

b) mail_location = mdbox:~/mdbox:ALT=/alt/%u:LAYOUT=fs:DIRNAME=dbox-Mails:MAILBOXDIR=mailboxes

mail_format = mdbox mail_root_path = ~/mdbox mail_alt_path = /alt/%u mail_dir_name = dbox-Mails mail_mailboxes_dir_name = mailboxes

Thoughts?