Ubuntu Manpage: msgchk - nmh's check for incoming email

NAME

       msgchk - nmh's check for incoming email

SYNOPSIS


       msgchk [-help] [-version] [-date | -nodate] [-notify all/mail/nomail ] [-nonotify all/mail/nomail ]
            [-host hostname] [-port portname/number] [-user username] [-sasl | -nosasl] [-saslmech mechanism]
            [-tls] [-initialtls] [-notls] [-certverify | -nocertverify] [-authservice service] [-snoop] [users
            ... ]

DESCRIPTION

The msgchk program checks all known mail drops for mail waiting for you. For those drops which have mail
for you, msgchk will indicate if it believes that you have seen the mail in question before.

The -notify type switch indicates under what circumstances msgchk should produce a message. The default
is -notify all which says that msgchk should always report the status of the users mail drop. Other
values for `type' include `mail' which says that msgchk should report the status of waiting mail; and,
`nomail' which says that msgchk should report the status of empty mail drops. The -nonotify type switch
has the inverted sense, so -nonotify all directs msgchk to never report the status of mail drops. This
is useful if the user wishes to check msgchk's exit status. A non-zero exit status indicates that mail
was not waiting for at least one of the indicated users.

If msgchk produces output, then the -date switch directs msgchk to print out the last date mail was read,
if this can be determined.

Using POP
msgchk will normally check all the local mail drops, but if the option “pophost:” is set in the mts
configuration file “mts.conf”, or if the -host hostname switch is given, msgchk will query this POP
service host as to the status of mail waiting. The -port switch specifies the port name or number used
to connect to the POP server. If unspecified, the default is “pop3”.

To specify a username for authentication with the POP server, use the -user username switch. The
credentials profile entry in mh-profile(5) describes the ways to supply a username and password.

For debugging purposes, there is also a switch -snoop, which will allow you to watch the POP transaction
take place between you and the POP server. If -sasl -saslmech xoauth2 is used, the HTTP transaction is
also shown.

If nmh has been compiled with SASL support, the -sasl switch will enable the use of SASL authentication.
Depending on the SASL mechanism used, this may require an additional password prompt from the user (but
the netrc file can be used to store this password, as described in mh-profile(5). The -saslmech switch
can be used to select a particular SASL mechanism.

If SASL authentication is successful, msgchk will attempt to negotiate a security layer for session
encryption. Encrypted traffic is labelled with `(encrypted)' and `(decrypted)' when viewing the POP
transaction with the -snoop switch; see post(8)'s description of -snoop for its other features.

If nmh has been compiled with OAuth support, the -sasl -saslmech xoauth2 switch will enable OAuth
authentication. The -user switch must be used, and the user-name must be an email address the user has
for the service, which must be specified with the -authservice service switch. Before using this, the
user must authorize nmh by running mhlogin and grant authorization to that account. See mhlogin(1) for
more details.

If nmh has been compiled with TLS support, the -tls and -initialtls switches will require the negotiation
of TLS when connecting to the remote POP server. The -tls switch will negotiate TLS as part of the
normal POP protocol using the STLS command. The -initialtls switch will negotiate TLS immediately after
the connection has taken place, before any POP commands are sent or received. Data encrypted by TLS is
labeled `(tls-encrypted)' and `(tls-decrypted)' with viewing the POP transaction with the -snoop switch.
The -notls switch will disable all attempts to negotiate TLS.

When using TLS the default is to verify the remote certificate and SubjectName against the local trusted
certificate store. This can be controlled by the -certverify and -nocertverify switches. See your
OpenSSL documentation for more information on certificate verification.

FILES

       $HOME/.mh_profile          The user profile
       /etc/nmh/mts.conf          nmh mts configuration file
       /var/mail/$USER            Location of mail drop

PROFILE COMPONENTS

       None

DEFAULTS

       `user' defaults to the current user
       `-date'
       `-notify all'

CONTEXT

       None

nmh-1.8                                            2016-11-02                                        MSGCHK(1mh)