Frankly, I was surprised when Mark said that FETCH should never return a tagged NO and that the preferred approach was to dummy up a note's structure when running into difficulty. I sure didn't get that from reading the RFC.
The whole point of IMAP is that a client is supposed to be able to depend upon the server. If a server could send an tagged NO to a FETCH, then there would be no need for a serverto implement ENVELOPE, BODYSTRUCTURE, etc. -- just send a tagged NO and force the client to FETCH RFC822 and parse the message itself.
If the server has a situation in which it fails to be dependable to the client, then the server is broken.
If the server can't parse the message at least as well as the client (and preferably better), then the server is broken.
Question: What does a client do if asked to create an envelope from the following message header?
Date: monday
From: your friend
Answer: it dummies up a proper envelope structure as best it can with the data that there is, and probably issues some PARSE barf messages.
Corrolary answer: the server can do the exact same thing. The server is required to do this. Therefore, there is no need for the client to do it, because it was already done by the server.
I'm equally surprised at the rush to * BYE a client at the slightest hint of a problem. I guess I was naive to assume that clients might have enough intelligence to take alternate action if exposed to the full spectrum of the protocol ... Perry
Once again, with feeling...:
If that were the case, there would be no need for a server to implement ENVELOPE, BODYSTRUCTURE, etc. -- just send a tagged NO and force the client to FETCH RFC822 and parse the message itself.
-- Mark --
http://staff.washington.edu/mrc Science does not emerge from voting, party politics, or public debate. Si vis pacem, para bellum.
