Chapter 14 ■ pOp

261

the pOp-3 prOtOCOL

purpose: allow download of e-mail from inbox

Standard: rFC 1939 (May 1996)

runs atop: tCp/Ip

Default port: 110 (cleartext), 995 (SSL)

Libraries: poplib

Listing 14-1. A Very Simple POP Session

#!/usr/bin/env python3

Foundations of Python Network Programming, Third Edition

https://github.com/brandon-rhodes/fopnp/blob/m/py3/chapter14/popconn.py

import getpass, poplib, sys

def main():
if len(sys.argv) != 3:
print('usage: %s hostname username' % sys.argv[0])
exit(2)

hostname, username = sys.argv[1:]
passwd = getpass.getpass()

p = poplib.POP3SSL(hostname) # or "POP3" if SSL is not supported
try:
p.user(username)
p.pass(passwd)
except poplib.error_proto as e:
print("Login failed:", e)
else:
status = p.stat()
print("You have %d messages totaling %d bytes" % status)
finally:
p.quit()

if name == 'main':
main()

■ Caution although this program does not alter any messages, some pOp servers will nonetheless alter mailbox flags

simply because you connected. running the examples in this chapter against a live mailbox could cause you to lose

information about which messages are read, unread, new, or old. Unfortunately, that behavior is server dependent and

beyond the control of pOp clients. I strongly recommend running these examples against a test mailbox rather than your

live mailbox!