You sometimes find the need to run a protocol dialogue on the command line via telnet. I recently had to do this for POP3. In fact it’s quite simple if you follow the example below where lines starting with a plus are responses from the server:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 telnet my.pop.server 110 Trying 123.456.789.123... Connected to my.pop.server. Escape character is '^]'. +OK Hello there. user firstname.lastname@example.org +OK Password required. pass secret +OK logged in. list +OK POP3 clients that break here, they violate STD53. 1 2213 2 2823 . retr 1 +OK 2213 octets follow. [email content] . dele 1 +OK Deleted. quit +OK Bye-bye.
The answer of the server could have a slightly different text which differs from server to server. However the dialogue is still the same.
The most common command shows the list below
|quit||terminates the session and deletes messages marked for deletion|
|stat||statistics about total count and size of mails|
|list||list of mail and their size|
|retr no.||retrieve the content of mail with number no.|
|dele no.||mark mail no. for deletion|
|noop||no operation, returns an OK (useful to keep the connection up)|
|rset||resets all changes and marks|
|top no. lines||show the first lines of message number no.|
|user name||authenticate as user name|
|pass password||submit password for current user|
|uidl||show unique ID of each mail (this is used by your POP3 client if you like to keep the mail on the server)|