Mailutils pop
The mailutils pop command invokes an interactive POP3 client shell. It reads commands from the standard input, executes them and displays the results on the standard output. If the standard input is connected to a terminal, the readline and history facilities are enabled (provided that Mailutils is configured with GNU Readline).
The mailutils pop commands form two major groups. The POP3 protocol commands interact with the remote POP3 server and display responses obtained from it. These commands are named after their POP3 equivalents. Another group, internal commands, are used to configure the shell itself.
POP3 protocol commands
- connect [-tls] hostname [port]
- Open connection to hostname. If the -tls option is given, TLS encryption (also known as POPS protocol) will be used. If port argument is not given, the command uses port 110 for a plain POP connection or 995 for POPS (if -tls is given).
- stls
- Start TLS negotiation. This command is valid only after successful unencrypted connection has been initiated (using connect without -tls argument).
- user name
- Send user name to the server. The pass command must follow.
- pass [password]
- Send password. This command is valid only after user. If the password argument is omitted, the shell will ask you to enter it. While entering, both echoing and history recording will be disabled. Use this to avoid compromising your password.
- apop user [password]
- Authenticate with APOP. If the password argument is omitted, you will be asked to supply it. While entering, both echoing and history recording will be disabled.
- capa [-reread] [name...]
- List server capabilities. Any number of name arguments is accepted. If given, the shell will display only the named capabilities, otherwise it displays entire list. By default capa reuses the response of its previous invocation (if there was any), instead of resending the CAPA command to the server. To force it do so, use the -reread option.
- noop
- Send a no operation.
- stat
- Get the mailbox size and number of messages in it.
- uidl [number]
- Shows unique message identifiers. Without arguments, shows identifiers for each message in the mailbox. If number is given, the command returns the UIDL of that particular message only.
- list [number]
- Lists messages. See above for the meaning of number. Each line of the produced listing contains describes a single message and contains at least the message number and size in bytes. Depending on the POP3 server implementation, additional fields may be present. For example, GNU Mailutils pop3d can also output number of lines in the message in the additional third field.
- retr number
- Retrieve a message.
- top msgno [number]
- Display message headers and first number (default 5) lines of its body.
- dele number
- Mark message for deletion.
- rset
- Remove deletion marks.
- quit
- Quit pop3 session.
- disconnect
- Close existing connection.
Internal commands
- verbose [on|off|mask|unmask] [secure [payload]]
Control output verbosity. Without arguments the verbose command shows current settings. The argument off (the default) turns off all additional output. The verbose on command enables POP3 protocol tracing output. Additional arguments can be used to provide more verbosity. The secure argument enables display of user passwords in the trace output and the payload enables showing payload data (e.g. response body sent in the reply to RETR command, etc.) Thus, the full diagnostics output is obtained by
verbose on secure payload
The mask and unmask argument allow to disable and enable such additional verbosity. For example, supposing the command above is in action, the following command will suppress the display of user passwords in the traces:
verbose mask secure
Similarly, verbose unmask secure will turn it back again.
- prompt string
- Set command prompt. The argument can contain variable references in the following forms:
$name
${name}
where name is the variable name. Such references are expanded to the actual value of the variable at the time of expansion. The following variables are defined:
| Variable | Expansion |
|---|---|
| user | Login name of the authenticated POP3 user. If the session is not authenticated yet, expands to [nouser]. |
| host | Name of the remote host, or [nohost] if no connection is established. |
| program-name | Name of the program, as typed on the command line to invoke it. |
| canonical-program-name | mailutils |
| package | Mailutils |
| version | Mailutils version number |
| status | Session status. One of: disconnected, connected or logged in. |
For example:
prompt "[${user}@$host] "
Notice the use of quotes to include the space character in the prompt.
- exit
- Exit the program.
- help [command]
- Without arguments displays a list of commands with possible arguments and short descriptions.
- With one argument, displays a terse description for the given command.
- ? [command]
- A synonym for help.
- history
- Shows command history.
