MH-MAIL(5) RISC/os Reference Manual MH-MAIL(5)
NAME
mh-mail - message format for MH message system
SYNOPSIS
any MH command
DESCRIPTION
MH processes messages in a particular format. It should be
noted that although neither Bell nor Berkeley mailers pro-
duce message files in the format that MH prefers, MH 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 messages.
Messages are expected to consist of lines of text. Graphics
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 message
consists of a block of information in a rigid format, fol-
lowed 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 consecutive newline
characters. Within MH, 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 keyword
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
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"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) sig-
nals 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 considered
meaningful to various MH programs.
Date:
Added by post (8), contains date and time of the
message's entry into the 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). Replies are typically directed to
addresses in the "Reply-To:" or "From:" field (the
former has precedence if present).
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. Replies are never sent to addresses
in the "Sender:" field.
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 reci-
pients are not listed. MH uses an encapsulation method
for blind copies, see send (1).
Fcc:
Causes post (8) to copy the message into the specified
folder for the sender, if the message was successfully
given to the transport system.
Message-ID:
A unique message identifier added by post (8) if the
`-msgid' flag is set.
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MH-MAIL(5) RISC/os Reference Manual MH-MAIL(5)
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
/usr/mail/$USER Location of mail drop
PROFILE COMPONENTS
None
SEE ALSO
Standard for the Format of ARPA Internet Text Messages (aka
RFC-822)
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DEFAULTS
None
CONTEXT
None
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