On 30 Aug 2019, at 13.44, Domenico Pastore via dovecot <dovecot@dovecot.org> wrote:

Hello,

i have update dovecot from version 2.2.15 to 2.3.7.2.
I have a problem with mine java software because there is a different
response when open connection to doveadm.

I need open socket to doveadm for get imap quota of a mailbox.

With version 2.2.15:
# telnet 192.160.10.4 924
Trying 192.160.10.4...
Connected to 192.160.10.4.
Escape character is '^]'.
-


With version 2.3.7.2:
# telnet 192.160.10.3 924
Trying 192.160.10.3...
Connected to 192.160.10.3.
Escape character is '^]'.


The difference is "-" character. The version 2.3.7 not respond with "-"
character after opening the connection.

Is it possible to add the character again with a parameter?

Why did doveadm's answer change?

It got changed as part of some other doveadm protocol changes. The change was somewhat accidental though and we didn't notice the difference. Anyway, practically this shouldn't have made any difference if the code was implemented as was described in https://wiki.dovecot.org/Design/DoveadmProtocol It says that the client needs to send VERSION first, and as a reply it receives the "+" or "-" line. So it was more of a bug that previous Dovecot versions sent the +/- line too early. I added a note about this to the wiki page though.