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Re: [Cbor] Why 0x42_4F_52 (was Re: 🔔 WG adoption call on draft-richardson-cbor-file-magic)

Michael Richardson <mcr@sandelman.ca> Thu, 18 February 2021 20:00 UTC

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From: Michael Richardson <mcr@sandelman.ca>
To: Laurence Lundblade <lgl@island-resort.com>, cbor@ietf.org
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Subject: Re: [Cbor] =?utf-8?b?V2h5IDB4NDJfNEZfNTIgKHdhcyBSZTog8J+UlCBXRyBh?= =?utf-8?q?doption_call_on_draft-richardson-cbor-file-magic=29?=
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Laurence Lundblade <lgl@island-resort.com> wrote:
    > protocol characteristics, so maybe there is no relation at all. Maybe
    > we define a new tag that indicates the file is an EAT and that is never
    > sent over the wire?

That's why the CBOR Sequence: if you want the mark in the file, but not on
the wire.

I think that 0xd9d9f6 or 0xd9d9f8 could be used for CBOR Sequence, and it
would also not be valid UTF-8.  While "0xd9" is a valid first byte of a three
byte sequence, 0xd9 is not a valid second byte.

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