pop3d - POP3 server
/usr/sbin/pop3d [-d] [-s] [-t trace-file] [-T timeout]
-d Sets the socket to debugging and turns on debugging. All debugging
information is saved using syslogd.
-s Turns on statistics logging using syslogd(8). At the end of each pop3d
session, the following information is logged: username, number of mes-
sages deleted, number of bytes deleted, number of message left on
server, number of bytes left on server.
Turns on debugging and saves the trace information in trace-file using
the fprintf(3) command.
When the server is waiting for a command to arrive from the client, it
times out after the specified number of seconds and terminates the ses-
sion. This avoids having pop3d processes hang forever waiting for com-
mand input from clients which have terminated abnormally. A small value
is acceptable for small to medium networks where the network delay is
within a few seconds. In this case 15-30 seconds is not unreasonable.
Networks with large delays in sending packets (for example, SLIP links)
may require a larger value. In this case 300 seconds (5 minutes) is
The pop3d server is an implementation of the Post Office Protocol Version 3
from Qualcomm, Incorporated. It provides remote users with the ability to
manage electronic mail on a UNIX system.
The operating system supports the following types of authentication for the
pop3d server: UNIX authentication using the /etc/passwd file, Authenticated
POP (APOP), and enhanced security using C2. The default is UNIX authentica-
To enable APOP authentication for a user, you must add the user to the
mailauth database. See mailauth(8) and the Network Administration: Services
manual for more information.
To use C2 secure authentication, you must configure your system to use C2
security. See secconfig(8) and the Security guide for more information.
The pop3d server uses the syslog daemon to keep a record of its activities.
Messages are logged in the /var/adm/syslog.dated/date/mail.log file.
The pop3d program will log debugging information when the -d parameter is
specified after its invocation in the inetd.conf file. Care should be
exercised in using this option since it generates considerable output in
the mail.log file. Alternatively, the -t file-name option will place
debugging information into file file-name using fprintf instead of syslog.
You can confirm that the POP server is running by opening a telnet session
to port 110. For example:
% telnet myhost 110
Connected to myhost.berkeley.edu.
Escape character is '^]'.
+OK UCB Pop server (version 1.6) at myhost starting.
+OK Pop server at myhost.berkeley.edu signing off.
Connection closed by foreign host.
The server implements two extended commands:
+ XTND XMIT
Sends a mail message using /usr/sbin/sendmail.
+ XTND XLIST header [num]
Extracts and returns the specified header line for the specified mes-
sage number. If the num parameter is missing, the command returns the
header line for all the messages that are not currently marked for
Note that this implementation of Qualcomm's POP3 server does not support
Server Mode, Kerberos authentication, or the bulletin feature.
POP program invocation
mail logging file
Commands: inetd(8), mailauth(8), mailusradm(8), secconfig(8)
Network Administration: Services