Does POP3 split between read and unread messages

Question

I work with Perl and use Net::POP3 ...

My code is able to receive all emails, but I could not find any method in the documentation that can distinguish between read and unread messages.

IMAP does this, so I wanted to know if this applies to POP3?

The PS :: ping() method in Net::POP3 not listed as a Net::POP3 feature

Answer 1

With POP3 it is not possible to distinguish between read or unread. It can only retrieve and delete messages. All messages that were not selected by the client (who remembers it himself) are regarded by the client as not new if he retrieves new messages. The server does not care about the state of the message. He just gives you all the messages he has.

From Wikipedia :

POP supports simple download and deletion requirements for accessing remote mailboxes (called maildrop in POP RFC). [3] Although most POP clients have the option of leaving mail on the server after downloading, email clients using POP usually connect, receive all messages, save them to the user's PC as new messages, delete them from the server, and then disconnect. Other protocols, in particular IMAP, (Internet Protocol for Access to Messages) provide a more complete and complex remote access to typical operations with mailboxes.