MH-MAIL(5)
NAME
mh-mail - message format for nmh message system
SYNOPSIS
any nmh command
DESCRIPTION
nmh processes messages in a particular format. It should
be noted that although neither Bell nor Berkeley mailers
produce message files in the format that nmh prefers, nmh
can read message files in that antiquated format.
Each user possesses a mail drop box which initially
receives all messages processed by post (8). Inc (1) will
read from that drop box and incorporate the new messages
found there into the user's own mail folders (typically
`+inbox'). The mail drop box consists of one or more mes-
sages.
Messages are expected to consist of lines of text. Graph-
ics and binary data are not handled. No data compression
is accepted. All text is clear ASCII 7-bit data.
The general "memo" framework of RFC-822 is used. A mes-
sage consists of a block of information in a rigid format,
followed by general text with no specified format. The
rigidly formatted first part of a message is called the
header, and the free-format portion is called the body.
The header must always exist, but the body is optional.
These parts are separated by an empty line, i.e., two con-
secutive newline characters. Within nmh, the header and
body may be separated by a line consisting of dashes:
To:
cc:
Subject:
--------
The header is composed of one or more header items. Each
header item can be viewed as a single logical line of
ASCII characters. If the text of a header item extends
across several real lines, the continuation lines are
indicated by leading spaces or tabs.
Each header item is called a component and is composed of
a keyword or name, along with associated text. The key-
word begins at the left margin, may NOT contain spaces or
tabs, may not exceed 63 characters (as specified by
RFC-822), and is terminated by a colon (`:'). Certain
components (as identified by their keywords) must follow
rigidly defined formats in their text portions.
The text for most formatted components (e.g., "Date:" and
"Message-Id:") is produced automatically. The only ones
entered by the user are address fields such as "To:",
"cc:", etc. Internet addresses are assigned mailbox names
and host computer specifications. The rough format is
"local@domain", such as "MH@UCI", or "MH@UCI-ICSA.ARPA".
Multiple addresses are separated by commas. A missing
host/domain is assumed to be the local host/domain.
As mentioned above, a blank line (or a line of dashes)
signals that all following text up to the end of the file
is the body. No formatting is expected or enforced within
the body.
Following is a list of header components that are consid-
ered meaningful to various nmh programs.
Date:
Added by post (8), contains date and time of the mes-
sage's entry into the mail transport system.
From:
Added by post (8), contains the address of the author
or authors (may be more than one if a "Sender:" field
is present). For a standard reply (using repl), the
reply address is constructed by checking the follow-
ing headers (in this order): "Mail-Reply-To:",
"Reply-To:", "From:", "Sender:".
Mail-Reply-To:
For a standard reply (using repl), the reply address
is constructed by checking the following headers (in
this order): "Mail-Reply-To:", "Reply-To:", "From:",
"Sender:".
Mail-Followup-To:
When making a "group" reply (using repl -group), any
addresses in this field will take precedence, and no
other reply address will be added to the draft. If
this header is not available, then the return
addresses will be constructed from the "Mail-
Reply-To:", or "Reply-To:", or "From:", along with
adding the addresses from the headers "To:", "cc:",
as well as adding your personal address.
Reply-To:
For a standard reply (using repl), the reply address
is constructed by checking the following headers (in
this order): "Mail-Reply-To:", "Reply-To:", "From:",
"Sender:".
Sender:
Added by post (8) in the event that the message
already has a "From:" line. This line contains the
address of the actual sender.
To:
Contains addresses of primary recipients.
cc:
Contains addresses of secondary recipients.
Bcc:
Still more recipients. However, the "Bcc:" line is
not copied onto the message as delivered, so these
recipients are not listed. nmh uses an encapsulation
method for blind copies, see send (1).
Fcc:
Causes post (8) to copy the message into the speci-
fied folder for the sender, if the message was suc-
cessfully given to the transport system.
Message-ID:
A unique message identifier added by post (8) if the
`-msgid' flag is set.
Subject:
Sender's commentary. It is displayed by scan (1).
In-Reply-To:
A commentary line added by repl (1) when replying to
a message.
Resent-Date:
Added when redistributing a message by post (8).
Resent-From:
Added when redistributing a message by post (8).
Resent-To:
New recipients for a message resent by dist (1).
Resent-cc:
Still more recipients. See "cc:" and "Resent-To:".
Resent-Bcc:
Even more recipients. See "Bcc:" and "Resent-To:".
Resent-Fcc:
Copy resent message into a folder. See "Fcc:" and
"Resent-To:".
Resent-Message-Id:
A unique identifier glued on by post (8) if the
`-msgid' flag is set. See "Message-Id:" and
"Resent-To:".
Resent:
Annotation for dist (1) under the `-annotate' option.
Forwarded:
Annotation for forw (1) under the `-annotate' option.
Replied:
Annotation for repl (1) under the `-annotate' option.
FILES
/var/spool/mail/$USER Location of mail drop
PROFILE COMPONENTS
None
SEE ALSO
RFC-822:Standard for the Format of ARPA Internet Text Mes-
sages
DEFAULTS
None
CONTEXT
None