On Mar 5, 16:53, Ned Freed wrote:
Hmmm... Interesting. Wouldn't it be nice if we had a file lying
around somewhere that listed all of the email headers ever invented.
Then we could look at that to make sure we aren't reinventing wheels.
I'm working on compiling such a document now. It will be strictly
informational
and takes no position on the appropriateness of anything.
Perhaps it would be too much work or not even useful to list *all*
headers, but maybe at least the headers defined in the STD series,
STD-to-be's, RFCs and Internet-Drafts. Is there such a list already?
Not that I know of. If anyone has one please let me know...
Ned
-- End of excerpt from Ned Freed <NED(_at_)sigurd(_dot_)innosoft(_dot_)com>
That is one of the few things missing from ASSIGNED NUMBERS that should
be in that document. Not even all of the RFC defined headers are in
one place, not to mention all of the sendmail defined things.
I started working on a collection also.
I can't put my finger on the most recent version I once posted to
comp.mail.headers, but here is what I could find right now.
I had wanted to find more info on non rfc defined de-facto (semi-)standard
headers before I did anything else with it. But the first pass was to
just to collect all of the RFC references I could find.
There are probably more since I started this! I haven't had time to
keep up on it lately.
===============================================================================
Steven D. Majewski University of Virginia
sdm7g(_at_)Virginia(_dot_)EDU Box 449 Health Sciences Center
Voice: (804)-982-0831 1300 Jefferson Park Avenue
FAX: (804)-982-1616 Charlottesville, VA 22908
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
RFC822: Standard for ARPA Internet Text Messages:
Minimum Required:
Date:
From:
To: or Bcc:
destination:
To:
Resent-To:
Cc:
Resent-cc:
Bcc:
Resent-bcc:
optional field:
Message-ID:
Resent-Message-ID:
In-Reply-To:
References:
Keywords:
Subject:
Comments:
Encrypted:
Reply-To:
Other ( appended ):
Resent-Reply-To:
Resent-From:
Resent-Sender:
Resent-Date:
Return-path:
Received:
RFC1036: Standard for the interchange of Usenet Messages (News):
[ "Certain Headers are required, and certains other headers are optional. Any
unrecognized headers are allowed, and will be passed through unchanged."]
-Required Headers:
From:
Date:
Newsgroups: group.1[,group.2,...]
Subject:
Message-ID: <unique(_at_)full_domain_name>
Path:
-Optional Headers:
Followup-To:
Expires:
Reply-To:
Sender:
References:
Control:
Distribution:
Keywords:
Summary:
Approved:
Lines:
Xref: (local info only, don't send)
Organization:
RFC1049: A Content-type header field for Internet Messages:
defines
Content-Type: { POSTSCRIPT | SCRIBE | SGML | TROFF | DVI | X-atom }
RFC1154: Encoding Header Field for Internet Messages:
defines
Encoding:
RFC1341: MIME:Multipurpose Internet Mail Extensions
MIME-Version:
Content-Type:
Content-Transfer-Encoding:
Content-ID:
Content-Description:
---------
Are "Status:" and "Precedence:" defined somewhere ?
Reply-Receipt-To: appears to be a sendmail invention. ( any others? )
What are the common (and FUNCTIONAL, i.e. not just decorative) X-extensions:?
X-Mailer:
X-Status: ( is it the same as Status: ? )
There are a lot of Gateway produced X-lines:
X-VMS-From:
X-VMS-xxx: ( keeps original VMS mail headers. )
???
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RFC 1327 Mapping between X.400(1988) and RFC 822 May 1992
2.2. RFC 822
RFC 822 does not explicitly define service elements, as distinct from
protocol elements. However, all of the RFC 822 header fields, with
the exception of trace, can be regarded as corresponding to implicit
RFC 822 service elements.
2.2.1. Origination in RFC 822
A mechanism of mapping, used in several cases, is to map the RFC 822
header into a heading extension in the IPM (InterPersonal Message).
This can be regarded as partial support, as it makes the information
available to any X.400 implementations which are interested in these
services. Communities which require significant RFC 822 interworking
are recommended to require that their X.400 User Agents are able to
display these heading extensions. Support for the various service
elements (headers) is now listed.
Date:
Supported.
From:
Supported. For messages where there is also a sender field,
the mapping is to "Authorising Users Indication", which has
subtly different semantics to the general RFC 822 usage of
From:.
Sender:
Supported.
Reply-To:
Supported.
To: Supported.
Cc: Supported.
Bcc: Supported.
Message-Id:
Supported.
In-Reply-To:
Supported, for a single reference. Where multiple
references are given, partial support is given by mapping to
"Cross Referencing Indication". This gives similar
semantics.
References:
Supported.
Keywords:
Supported by use of a heading extension.
Subject:
Supported.
Comments:
Supported by use of an extra body part.
Encrypted:
Supported by use of a heading extension.
Resent-*
Supported by use of a heading extension. Note that
addresses in these fields are mapped onto text, and so are
not accessible to the X.400 user as addresses. In
principle, fuller support would be possible by mapping onto
a forwarded IP Message, but this is not suggested.
Other Fields
In particular X-* fields, and "illegal" fields in common
usage (e.g., "Fruit-of-the-day:") are supported by use of
heading extensions.
2.2.2. Reception by RFC 822
This considers reception by an RFC 822 User Agent of a message
originated in an X.400 system and transferred across a gateway. The
following standard services (headers) may be present in such a
message:
Date:
From:
Sender:
Reply-To:
To:
Cc:
Bcc:
Message-Id:
In-Reply-To:
References:
Subject:
The following non-standard services (headers) may be present. These
are defined in more detail in Chapter 5 (5.3.4, 5.3.6, 5.3.7):
Autoforwarded:
Content-Identifier:
Conversion:
Conversion-With-Loss:
Delivery-Date:
Discarded-X400-IPMS-Extensions:
Discarded-X400-MTS-Extensions:
DL-Expansion-History:
Deferred-Delivery:
Expiry-Date:
Importance:
Incomplete-Copy:
Language:
Latest-Delivery-Time:
Message-Type:
Obsoletes:
Original-Encoded-Information-Types:
Originator-Return-Address:
Priority:
Reply-By:
Requested-Delivery-Method:
Sensitivity:
X400-Content-Type:
X400-MTS-Identifier:
X400-Originator:
X400-Received:
X400-Recipients:
----------