public-inbox-pop3d - Man Page

POP3 server for sharing public-inboxes


  public-inbox-pop3d [OPTIONS]


public-inbox-pop3d provides a POP3 daemon for public-inbox. It uses options and environment variables common to all read-only public-inbox-daemon(8) implementations, but requires additional read-write storage to keep track of deleted messages on a per-user basis.

Like public-inbox-imapd(1), public-inbox-pop3d will never require write access to the directory where the public-inboxes are stored.

It is designed for anonymous access, thus the password is always anonymous (all lower-case).

Usernames are of the format:


Where $UUID is the output of the uuidgen(1) command.  Dash (-) characters in UUIDs are ignored, and [A-F] hex characters are case-insensitive.  Users should keep their UUIDs private to prevent others from deleting unretrieved messages. Users may switch to a new UUID at any time to retrieve previously-retrieved messages.

Historical slices of 50K messages are available by suffixing the integer $SLICE, where 0 is the oldest.


It may be run as a different user than the user running public-inbox-watch(1), public-inbox-mda(1), or public-inbox-fetch(1).

To save storage, "publicinbox.pop3state" only stores the highest-numbered deleted message


See common options in "OPTIONS" in public-inbox-daemon(8).

-l PROTOCOL://ADDRESS/?cert=/path/to/cert,key=/path/to/key
--listen PROTOCOL://ADDRESS/?cert=/path/to/cert,key=/path/to/key

In addition to the normal -l/--listen switch described in public-inbox-daemon(8), the PROTOCOL prefix (e.g. pop3:// or pop3s://) may be specified to force a given protocol.

For STARTTLS and POP3S support, the cert and key may be specified on a per-listener basis after a ? character and separated by ,. These directives are per-directive, and it's possible to use a different cert for every listener.

--cert /path/to/cert

The default TLS certificate for optional STARTTLS and POP3S support if the cert option is not given with --listen.

If using systemd-compatible socket activation and a TCP listener on port 995 is inherited, it is automatically POP3S when this option is given. When a listener on port 110 is inherited and this option is given, it automatically gets STARTTLS support.

--key /path/to/key

The default private TLS certificate key for optional STARTTLS and POP3S support if the key option is not given with --listen.  The private key may be concatenated into the path used by --cert, in which case this option is not needed.


Aside from publicinbox.pop3state, public-inbox-pop3d uses the same configuration knobs as public-inbox-nntpd(1), see public-inbox-nntpd(1) and public-inbox-config(5).


A directory containing per-user/mailbox account information; must be writable to the public-inbox-pop3d process.


The newsgroup name maps to a POP3 folder name.


Feedback welcome via plain-text mail to <>

The mail archives are hosted at <>, and <nntp://>, <nntp://4uok3hntl7oi7b4uf4rtfwefqeexfzil2w6kgk2jn5z2f764irre7byd.onion/inbox.comp.mail.public-inbox.meta>

See Also

git(1), git-config(1), public-inbox-daemon(8), public-inbox-config(5), public-inbox-nntpd(1), uuidgen(1)

Referenced By

public-inbox-config(5), public-inbox-daemon(8).

1993-10-02 public-inbox.git public-inbox user manual