Re: POP3 behavior on broken tcp connection

[Michael D'Errico <[e-mail]>]

I agree with Marshall that no messages should be deleted because
of a broken connection.

If we add the UIDL command as proposed, the problems of having
a connection break are solved along with the previously noted
problems related to LAST and the "Status:" hack.

I could probably add UIDL to my POP server in about a half hour
so I'm all for it.  Does anybody see it as being difficult to
add to theirs?

The following hypothetical scenario shows how UIDL can be used
by a client to figure out that it has already seen a message in
case it isn't obvious to someone:

	[client connects and logs in]
	C: STAT
	S: +OK 2 3826
	C: UIDL
	S: +OK
	S: 1 [e-mail]
	S: 2 [e-mail]
	S: .
	C: RETR 1
	S: +OK
	...
	S: .
	C: DELE 1
	S: +OK
	C: RETR 2
	S: +OK
	...
	[connection dies]

later....

	[client connects and logs in]
	C: STAT
	S: +OK 4 8477
	C: UIDL
	S: +OK
	S: 1 [e-mail]
	S: 2 [e-mail]
	S: 3 [e-mail]
	S: 4 [e-mail]
	S: .
	C: DELE 1
	S: +OK
	C: RETR 2
	S: +OK
	...

Notice that the client can immediately recognize that it has
retrieved the first message and can delete it immediately.


Michael D'Errico
[e-mail]