---
name: "popd"
section: "8mh"
platform: "linux"
package: "mh"
version: "6.8.4-JP-3.03-32.4"
release: "Debian 2.2 (Potato)"
platforms: ["linux"]
url: "https://new.carta.tech/popd/8mh"
---

# popd(8mh)

the POP server

## NAME

popd - the POP server

## SYNOPSIS

/usr/etc/popd \[-p portno\] (under /etc/rc.local)

## DESCRIPTION

The *popd* server implements the Post Office Protocol (version 3), as described in RFC1081 and RFC1082. Basically, the server listens on the TCP port named “pop” for connections and enters the POP upon establishing a connection. The \`-p' option overrides the default TCP port.

If the POP2 configuration option is defined, then the server also implements version 2 of the protocol.

If the APOP configuration option is defined, then the server supports a non-standard mechanism for identity-establishment in which authentication credentials are used to provide for origin authentication and reply protection, but which do not involve sending a password in the clear over the network. See [*popauth*(8)](/popauth/8.md) for more details. ^/usr/spool/pop/POP~^POP database None *Post Office Protocol - version 3* (aka RFC-1081),\
 *Post Office Protocol - version 3: Extended service offerings* (RFC-1082),\
 pop(5) None None For historical reasons, the *MH* POP defaults to using the port named “pop” (109) instead of its newly assigned port named “pop3” (110). See the POPSERVICE configuration option for more details.

Previous versions of the server (10/28/84) had the restriction that the POP client may retrieve messages for login users only. This restriction has been lifted, and true POB support is available (sending mail to a mailbox on the POP service host which does not map to a user-id in the password file).