.TH POST %manext8% 2016-10-17 "%nmhversion%"
.
.\" %nmhwarning%
.
.SH NAME
post \- deliver an nmh message
.SH SYNOPSIS
.HP 5
.na
.B %nmhlibexecdir%/post
.RB [ \-help ]
.RB [ \-version ]
.RB [ \-alias
.IR aliasfile ]
.RB [ \-filter
.IR filterfile ]
.RB [ \-nofilter ]
.RB [ \-format " | " \-noformat ]
.RB [ \-mime " | " \-nomime ]
.RB [ \-msgid " | " \-nomsgid ]
.RB [ \-messageid
.IR localname " | " random ]
.RB [ \-verbose " | " \-noverbose ]
.RB [ \-watch " | " \-nowatch ]
.RB [ \-width
.IR columns ]
.RB [ \-mts
.IR smtp " | " sendmail/smtp " | " sendmail/pipe ]
.RB [ \-sendmail
.IR program ]
.RB [ \-server
.IR servername ]
.RB [ \-port
.IR portname/number ]
.RB [ \-sasl ]
.RB [ \-nosasl ]
.RB [ \-saslmech
.IR mechanism ]
.RB [ \-user
.IR username ]
.RB [ \-tls ]
.RB [ \-initialtls ]
.RB [ \-notls ]
.RB [ \-snoop ]
.I file
.ad
.SH DESCRIPTION
.B post
is the default program called by
.B send
to deliver the message in
.I file
to local and remote users.
In fact, most of the features attributed to
.B send
in its manual page are performed by
.BR post ,
with
.B send
acting as a relatively simple preprocessor.
Thus, it is
.B post
which parses the various header fields, appends a
\*(lqDate:\*(rq line, and interacts with the mail transport system.
.B post
will not normally be called directly by the user, but can be replaced
by the user with a
.I postproc
profile component that will have
.I file
as its final argument.
See
.IR mh-profile (5)
for more information on postproc.
.PP
.B post
searches the \*(lqTo:\*(rq, \*(lqcc:\*(rq, \*(lqBcc:\*(rq,
\*(lqFcc:\*(rq, and \*(lqResent\-xxx:\*(rq header lines of the specified
message for destination addresses, checks these addresses for validity,
and formats them so as to conform to ARPAnet Internet Message Format
protocol, unless the
.B \-noformat
flag is set.  This will normally cause
\*(lq@\fIlocal\-site\fR\*(rq to be appended to each local destination
address, as well as any local return addresses.  The
.B \-width
.I columns
switch can be used to indicate the preferred length of the header
components that contain addresses.
.PP
If a \*(lqBcc:\*(rq field is encountered, its addresses will be used for
delivery, and the \*(lqBcc:\*(rq field will be removed from the message
sent to sighted recipients. The blind recipients will receive an entirely
new message with a minimal set of headers. The body of this new message
will contain a copy of the message sent to the sighted recipients, either
marked up with the indicator text "Blind-Carbon-Copy" or encapsulated
as a MIME digest.
.PP
If
.B \-filter
.I filterfile
is specified, then this copy is filtered (re-formatted) by
.B mhl
prior to being sent to the blind recipients.
Alternately, if the
.B \-mime
switch is given, then
.B post
will use the MIME rules for encapsulation.
.PP
If a \*(lqDcc:\*(rq field is encountered and the
.B sendmail/pipe
mail transport method is not in use, its addresses will be used for
delivery, and the \*(lqDcc:\*(rq field will be removed from the message. The
blind recipients will receive exactly the same message as the sighted
recipients. *WARNING* Recipients listed in the \*(lqDcc:\*(rq field receive no
explicit indication that they have received a \*(lqblind copy\*(rq.
This can cause blind recipients to
inadvertently reply to all of the sighted recipients of the
original message, revealing that they received a blind copy.
On the other hand, since a normal reply to a message sent
via a \*(lqBcc:\*(rq field
will generate a reply only to the sender of the original message,
it takes extra effort in most mailers to reply to the included
message, and so would usually only be done deliberately, rather
than by accident.
.PP
.B post
rejects any message that contains a \*(lqDcc:\*(rq field if the
.B sendmail/pipe
mail transport method is used.
.PP
The
.B \-alias
.I aliasfile
switch can be used to specify a file that post should read aliases from.
More than one file can be specified, with each being preceded by
.BR \-alias .
In any event, the primary alias file is read first.
.PP
The
.B \-msgid
switch indicates that a \*(lqMessage\-ID:\*(rq or
\*(lqResent\-Message\-ID:\*(rq field should be added to the header.
.PP
The
.B \-messageid
switch selects the style used for the part appearing after the @
in \*(lqMessage\-ID:\*(rq, \*(lqResent\-Message\-ID:\*(rq, and
\*(lqContent\-ID:\*(rq header fields.  The two acceptable options are
.B localname
(which is the default),
and
.BR random .
With
.BR localname ,
the local hostname is used.  With
.BR random ,
a random sequence of characters is used instead.  Note that the
.B \-msgid
switch must be enabled for this switch to have any effect.
.PP
The
.B \-verbose
switch indicates that the user should be informed of
each step of the posting/filing process.
.PP
The
.B \-watch
switch indicates that the user would like to watch the
transport system's handling of the message (e.g., local and \*(lqfast\*(rq
delivery).
.PP
Under normal circumstances,
.B post
uses the \*(lqFrom:\*(rq line in the message draft as the identity of
the originating mailbox.  A \*(lqFrom:\*(rq line is required in
all message drafts.  By default the message composition utilities such
as
.BR comp ,
.B repl
and
.B mhmail
will automatically place a \*(lqFrom:\*(rq line in the message draft.
There are two ways to override this behavior, however.
Note that they apply equally to \*(lqResent\-From:\*(rq lines in messages sent
with
.BR dist .
.PP
The first way is to supply a \*(lqSender:\*(rq line.  The value of this
field will be used as the originating mailbox identity when submitting the
message to the mail transport system.  If multiple addresses are
given in the \*(lqFrom:\*(rq line, a \*(lqSender:\*(rq line is
.BR required .
If an \*(lqEnvelope-From:\*(rq line is supplied when multiple addresses
are given in the \*(lqFrom:\*(rq line, a \*(lqSender:\*(rq header will
be generated using the value of the \*(lqEnvelope-From:\*(rq line,
.B if
the \*(lqEnvelope-From:\*(rq line is not blank.
.PP
The second way is to supply a \*(lqEnvelope-From:\*(rq line.  The value
of this field will be used as the originating mailbox identity when
submitting the message to the mail transport system.  This will override
both the value of the \*(lqFrom:\*(rq line and a \*(lqSender:\*(rq line
(if one is supplied).  The \*(lqEnvelope-From:\*(rq line is allowed to
have a blank value; if the value is blank, then the mail transport system
will be instructed to not send any bounces in response to the message.
Not all mail transport systems support this feature.
.PP
The mail transport system default is defined in
.I %nmhetcdir%/mts.conf
but can be overridden here with the
.B \-mts
switch.
.PP
If nmh is using
.B sendmail/pipe
or
.B sendmail/smtp
as its mail transport system, the
.B \-sendmail
switch can be used to override the default
.B sendmail
program.
.PP
If nmh is using the SMTP MTA, the
.B \-server
and
.B \-port
switches can be used to override the default mail server and port.
The default server is set with
.I servers
in
.IR %nmhetcdir%/mts.conf ,
and the default port is
.IR submission ,
587.
.PP
If
.B nmh
has been compiled with SASL support, the
.B \-sasl
and
.B \-nosasl
switches will enable and disable
the use of SASL authentication with the SMTP MTA.  Depending on the
SASL mechanism used, this may require an additional password prompt from the
user (but the
.I netrc
file can be used to store this password, as described in
.IR mh-profile (5).
The
.B \-saslmech
switch can be used to select a particular SASL mechanism,
and the
.B \-user
switch can be used to select an authorization userid to provide to SASL,
other than the default.  The credentials profile entry in
.IR mh-profile (5)
describes the ways to supply a username and password.
.PP
If SASL authentication is successful,
nmh
will attempt to negotiate a security layer for session encryption.
Encrypted data is labelled with `(sasl-encrypted)' and `(sasl-decrypted)' when
viewing the SMTP transaction with the
.B \-snoop
switch.
Base64-encoded data is wrapped with `b64<>'.
(Beware that the SMTP transaction may contain authentication information either
in plaintext or easily decoded base64.)
.PP
If
.B nmh
has been compiled with TLS support, the
.B \-tls
and
.B \-initialtls
switches will require the negotiation of TLS when connecting to the SMTP MTA.
The
.B \-tls
switch will negotiate TLS as part of the normal SMTP protocol
using the STARTTLS command.  The
.B \-initialtls
will negotiate TLS immediately after the connection has
taken place, before any SMTP commands are sent or received.  Encrypted data
is labelled with `(tls-encrypted)' and
`(tls-decrypted)' when viewing the SMTP transaction with the
.B \-snoop
switch.
Base64-encoded data is wrapped with `b64<>'.
(Beware that the SMTP transaction may contain authentication information either
in plaintext or easily decoded base64.)
The
.B \-notls
switch will disable all attempts to negotiate TLS.
.PP
If port 465 is specified and none of the TLS switches were enabled,
.B \-initialtls
will be implied if TLS support was compiled in.  Though port 465 for
SMTPS (SMTP over SSL) was deregistered by IANA in 1998, it is still
used for that service.
.PP
.B post
filters out header lines with names beginning with \*(lqNmh-\*(rq
(case insensitive) from the message draft.
Those lines are reserved for internal
.B nmh
use.
.SH FILES
.fc ^ ~
.nf
.ta \w'%nmhetcdir%/ExtraBigFileName  'u
^%nmhetcdir%/mts.conf~^nmh mts configuration file
^%nmhetcdir%/MailAliases~^global nmh alias file
^%bindir%/refile~^Program to process Fcc:s
^%nmhlibexecdir%/mhl~^Program to process Bcc:s
.fi
.SH "PROFILE COMPONENTS"
.B post
does
.I not
consult the user's
.I \&.mh_profile
.SH "SEE ALSO"
.IR mhmail (1),
.IR send (1),
.IR mh\-mail (5),
.IR mh\-alias (5),
.IR mh\-profile (5),
.IR mh\-tailor (5)
.PP
.I "Standard for the Format of ARPA Internet Text Messages"
(RFC 822)
.SH DEFAULTS
.nf
.RB ` \-alias "' defaults to %nmhetcdir%/MailAliases"
.RB ` \-format '
.RB ` \-nomime '
.RB ` \-nomsgid '
.RB ` "\-messageid\ localname" '
.RB ` \-noverbose '
.RB ` \-nowatch '
.RB ` "\-width\ 72" '
.RB ` \-nofilter '
.fi
.SH CONTEXT
None
.SH BUGS
\*(lqReply\-To:\*(rq fields are allowed to have groups in them according
to the RFC 822 specification, but
.B post
won't let you use them.