In <200801250228(_dot_)50997(_dot_)Mark(_dot_)Martinec+ietf(_at_)ijs(_dot_)si>
Mark Martinec <Mark(_dot_)Martinec+ietf(_at_)ijs(_dot_)si> writes:
Here is my attempt:
A bit wordy, and not quite correct, so some emendations below:
3.6. Field definitions
The header fields of a message are defined here. All header fields
have the same general syntactic structure: A field name, followed by
a colon, followed by the field body. The specific syntax for each
header field is defined in the subsequent sections.
Note: In the ABNF syntax for each field in subsequent sections,
each field name is followed by the required colon. However, for
brevity sometimes the colon is not referred to in the textual
description of the syntax. It is, nonetheless, required.
Note: all structured and unstructured header field bodies defined
in this document allow an optional WSP as their first character.
It became a customary practice to place one SP there. Some other
protocols such as Netnews require such a SP, ...
^
[USEFOR (or RFC1036 at a pinch)], including NNTP [RFC3977],
........ so a gateway needs
to modify header fields which do not conform to that stricter
specification. ..........
^^^^^^^^^^^^^^^^^^^^^^^^^
... and gateways cannot be relied upon to insert it .....
....... Moreover, some popular electronic mail message
transportation programs like to modify header fields to conform to
their idea of a pretty header field. Such necessary or frivolous
transformations can be detected by recipients and may rise suspicion
about message integrity or authenticity. ......
^^^^^^^^^^^^^^^^^^^^^^^^^
[I would be happy to omit that bit, but it does no harm]
...... Continuance of the practice
by implementors to place one SP at the beginning of newly generated
header field bodies is encouraged in order to facilitate
interoperability.
+1
It is important to note that the header fields are not guaranteed to
be in a particular order. ...
--
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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