[aprssig] UTF-8 for APRS (testing)

[Matti Aarnio]

On Wed, Sep 23, 2009 at 05:58:55AM -0700, Curt, WE7U wrote:
> On Wed, 23 Sep 2009, Matti Aarnio wrote:
>
>> digi_ned is binary transparent on payload, and it has a built in limit
>> of 256 bytes as max payload size.
>
> Great!
>
> A 256-byte limit applies only to frame size for connected packets in
> the AX.25 spec (non-APRS).  This would be a good time to fix that
> limit in digi_ned, perhaps making it configurable by the user?  That
> would help prepare for future generation fast networks.

Hi Curt,

In accordance to philosophy of "it compiles, ship it!" I am announcing
a patch set to digi_ned to permit more than 256 byte AX.25 frames to be
digipeated.

This makes those limits coherent among themselves, a number of places
define char arrays with explicite number 256 as size.  Other places use
definition of  MAX_DATA_LENGTH...

Applying this diff on top of digi_ned-0.3.9 will use everywhere
that definition, plus enlarge the hard limits to 2 kB, which should
be "enough" for any use.

  http://ham.zmailer.org/oh2mqk/aprs/digi_ned-0.3.9-mqk.diff

On overall  digi_ned is deeply a MS DOS program, which has just barely
been ported to Linux as well as Windows.  Its program structure is based
on "master program BUSY-polls everything" methodology of DOS programs.
In UNIX (and Windows) the style is: "we setup event watchers, and wake
up to do our bidding when an event happens".
No CPU burning, no IO churning...

But if that is representative of _best_ that there currently is, ...
Sigh, the level of accepted "best" is rather low :-/

I do hope there exists something better without me going to write one
from scratch, but the digi_ned needs heavy engineering to improve.
.. and if it were dependent upon me, predict and telemetry would be
dropped from it.  They are business of separate programs, not digipeater.
At DOS time everying was integrated, but do remember that UNIX begun
far before and in far smaller machines that those first DOS machines
were, and there was already multitasking!  
(oops, I am rambling)

> -- 
> Curt, WE7U.                         <http://www.eskimo.com/~archer>
>    APRS:  Where it's at!                    <http://www.xastir.org>
-- 
73 de Matti, OH2MQK