[Dovecot] imap support question

OK, I'm actually trying to write something which interacts with IMAP.

I'm trying to run the FETCH command and it goes OK, but I'm wondering how I might be able to call both RFC822.SIZE and BODY[HEADERS.FIELDS(..) in the same call. Right now I'm only able to get this to work with two calls to the server. I was hoping to avoid making two calls.

Any suggestions?

(I realize it isn't exactly "on topic" for the mailing list, but I can't think of any list I'm on that's even close to the topic)