[aprssig] !x! (was: IS-to-RF proposal (rev b))

Heikki Hannikainen hessu at hes.iki.fi
Tue Jan 3 08:48:47 EST 2012


On Tue, 3 Jan 2012, Jason KG4WSV wrote:

> On Tue, Jan 3, 2012 at 3:18 AM, Heikki Hannikainen <hessu at hes.iki.fi> wrote:
>> It is implemented for object descriptions (and items and other position
>> formats), but as described above, it needs to go in the beginning of the
>> comment. It might make more sense to have it in the end so it would not
>> affect the readability.
>
> The proposed spec says "Any packet containing this string should not
> be archived".  Your requirement for the position of !x! does not meet
> spec.
>
> The proposed spec says "should" and this certainly seems like a case
> for a "shall" instead of "should".

You're right. I do not intend to conform with that sort of proposed spec 
(cut 'n' paste from my previous email):

For positions I probably thought it could be a bad idea to allowed it to 
appear anywhere - it might be valid encoded thing in some APRS data 
extension, or could appear in someone's comment text accidentally.

!x! can probably appear in some valid compressed packets given the right 
coordinates.

Besides, it's slower to scan the whole packet for strings than to check if 
it's in the end of the comment.

Given the very small current usage of !x! it's easy to adjust the spec to 
make it right.

   - Hessu





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