[Dovecot] RFC 2822 - message-id

Piotr KUCHARSKI chopin at sgh.waw.pl
Fri Nov 10 10:42:02 UTC 2006

On Fri, Nov 10, 2006 at 05:35:05AM -0500, Tom Allison wrote:
> I was porting some email from one imap server location to another and ran 
> into a feature of something.  One of them writes message-id as 'Message-Id' 
> and the other writes it as 'Message-ID'.  Because of this, all the messages 
> are forever different.
> All mail is delivered from postfix and will be in the future.
> But I'm asking which of these syntaxes is correct or if there is a 
> right/wrong way of writing the headers?  RFC2822 doesn't come right out and 
> say it, but all the examples therein are "Message-ID".
> RFC 822 says they are all the same.
> Both?

Quote from RFC2822:

1.2.2. Syntactic notation

   This standard uses the Augmented Backus-Naur Form (ABNF) notation
   specified in [RFC2234] for the formal definitions of the syntax of
   messages.  Characters will be specified either by a decimal value
   (e.g., the value %d65 for uppercase A and %d97 for lowercase A) or by
   a case-insensitive literal value enclosed in quotation marks (e.g.,
   "A" for either uppercase or lowercase A).  See [RFC2234] for the full
   description of the notation.

Hence the case is irrelevant for header names.


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