usefor-usefor-02 November 2004
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2.2 Headers
All headers in a news article are compliant with [RFC2822], however
this specification is less permissive in what can be generated and
accepted by news agents. The syntax allowed for news articles is a
strict subset of the "Internet Message Format", making all messages
compliant with this specification inherently compliant with
[RFC2822]. Note however that the converse is not guaranteed to be
true in all cases.
General rules which apply to all headers (even those documented in
[RFC2822] and [RFC2045]) are listed below and those that apply to
specific headers are described in the relevent sections of this
document.
o All agents MUST generate headers so that at least one space
immediately follows the ':' separating the header name and the
header contents (for compatibility with deployed software). News
agents MAY accept headers which do not contain the required space.
o The header contents of every header line (including the first and
any that are subsequently folded) MUST contain at least one
non-whitespace character.
NOTE: This means that no header content defined by or
referenced by this document can be empty. As a result, this
document updates the <unstructured> construct from Section
3.2.6 of [RFC2822] as follows:
unstructured = 1*( [FWS] utext ) [FWS]
o Compliant software MUST NOT generate (but MAY accept) headers of
more than 998 octets. This is the only limit on the length of a
header line prescribed by this standard. However, specific rules
to the contrary may apply in particular cases (for example,
according to [RFC2047] header lines containing encoded-words are
limited to 76 octets). [USEAGE] includes suggested limits for
convenience of display by user agents.
NOTE: There is NO restriction on the number of lines into which
a header may be split, and hence there is NO restriction on the
total length of a header (in particular it may, by suitable
folding, be made to exceed the 998 octets restriction
pertaining to a single header line).
o The character set for headers is US-ASCII. Where the use of
non-ASCII characters is required, they MUST be encoded using the
MIME mechanisms defined in [RFC2045] and [RFC2231].
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#Diff to first older
--- ../usefor-article-13/Headers.out May 2004
+++ ../usefor-usefor-02/Headers.out November 2004
@@ -1,9 +1,45 @@
-4.2. Headers
+2.2 Headers
- The order of headers in an article is not significant. However,
- posting agents are encouraged to put mandatory headers (section 5)
- first, followed by optional headers (section 6), followed by
- experimental headers and headers not defined in this standard or its
- extensions. Relaying agents MUST NOT change the order of the headers
- in an article.
+ All headers in a news article are compliant with [RFC2822], however
+ this specification is less permissive in what can be generated and
+ accepted by news agents. The syntax allowed for news articles is a
+ strict subset of the "Internet Message Format", making all messages
+ compliant with this specification inherently compliant with
+ [RFC2822]. Note however that the converse is not guaranteed to be
+ true in all cases.
+
+ General rules which apply to all headers (even those documented in
+ [RFC2822] and [RFC2045]) are listed below and those that apply to
+ specific headers are described in the relevent sections of this
+ document.
+
+ o All agents MUST generate headers so that at least one space
+ immediately follows the ':' separating the header name and the
+ header contents (for compatibility with deployed software). News
+ agents MAY accept headers which do not contain the required space.
+ o The header contents of every header line (including the first and
+ any that are subsequently folded) MUST contain at least one
+ non-whitespace character.
+ NOTE: This means that no header content defined by or
+ referenced by this document can be empty. As a result, this
+ document updates the <unstructured> construct from Section
+ 3.2.6 of [RFC2822] as follows:
+
+ unstructured = 1*( [FWS] utext ) [FWS]
+
+ o Compliant software MUST NOT generate (but MAY accept) headers of
+ more than 998 octets. This is the only limit on the length of a
+ header line prescribed by this standard. However, specific rules
+ to the contrary may apply in particular cases (for example,
+ according to [RFC2047] header lines containing encoded-words are
+ limited to 76 octets). [USEAGE] includes suggested limits for
+ convenience of display by user agents.
+ NOTE: There is NO restriction on the number of lines into which
+ a header may be split, and hence there is NO restriction on the
+ total length of a header (in particular it may, by suitable
+ folding, be made to exceed the 998 octets restriction
+ pertaining to a single header line).
+ o The character set for headers is US-ASCII. Where the use of
+ non-ASCII characters is required, they MUST be encoded using the
+ MIME mechanisms defined in [RFC2045] and [RFC2231].