Re: POP3 fragile?

[Stainless Steel Rat <ratinox@peorth.gweep.net>]

* Florian Weimer <fw@deneb.enyo.de>  on Tue, 15 Jul 2003
| Does unwind-protect catch C-g?

Catch as in "mask the interrupt"?  I believe not.
Even if it does, the worst that can happen with stock pop3.el is that
you'll have a bunch of stuff in the crashbox and copies of those messages
on the server.

| I imagined that the client might send a QUIT while many, many messages
| are still buffered at the transport layer.  However, this is
| impossible; the protocol ensures implicit resynchronizes before each
| messages.

Exactly.  The POP protocols were designed to be both simple and robust
enough for the dumbest of MS-DOS mail clients.  They are quite tolerant of
client and link failures of various sorts.  As I said, the catastrophic
loss you experienced should not be possible unless the server is doing
something very badly broken.

Recent versions of qpopper can be configured to automatically issue DELE
commands after each successful RETR, to foil (ab)use of "leave mail on
server".  But even so, messages are not purged unless the client explicitly
issues a QUIT command and closes the session gracefully.  It may be that
you have a hacked POP server that expunges messages immediately after a
successful RETR.

-- 
Rat <ratinox@peorth.gweep.net>    \ Warning: pregnant women, the elderly, and
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