POP3 and "seen" flag

[Peter Hansen]

Miki Tebeka wrote:
> Is there a way to know in a POP session of a message was seen (old) or not
> (new)?

Define "seen".  It could be interpreted as either "TOP" or "RETR" having 
been executing for a message, or something like "this client has seen 
this message before" ... not sure what you mean.

In any case, the short answer is "no".

The longer answer is that _some_ POP3 servers provide non-standard 
support for this by doing things like adding a special header to the 
message, things like "X-Seen", which can be seen by using the TOP 
command.  This sort of thing is entirely non-standard and you can't rely 
on it in general, AFAIK.

A better approach would be to have your client software track the 
Message-ID header, but something tells me you are interpreting "seen" as 
meaning "anyone has RETRed the message", so that won't work either.

-Peter