The documentation for the Dovecot Dict Protocol in both the 2.3 and 2.4 mention that the server sends back a response for the HELLO command as part of a handshake.
The server then checks client’s protocol version and can either accept the handshake and proceed to response with OK or reject the HELLO and close the connection.
If the handshake is accepted by server, the optional extra values in the response line contain server’s major and minor protocol versions (tab separated). The client also checks the protocol version and can decide to close the connection if versions do not match.
However, after doing some tests with the protocol and digging into the code, it appears that the client is not expecting anything back from the server in response to HELLO.
Also, the tab escaping documentation says that CR is escaped using the l character when the code is actually escaping it with the n character.
The documentation for the Dovecot Dict Protocol in both the 2.3 and 2.4 mention that the server sends back a response for the HELLO command as part of a handshake.
However, after doing some tests with the protocol and digging into the code, it appears that the client is not expecting anything back from the server in response to HELLO.
Also, the tab escaping documentation says that CR is escaped using the
lcharacter when the code is actually escaping it with thencharacter.