[Xastir] Help with Acks

[Tom Russo]

On Thu, Sep 27, 2012 at 10:06:04AM -0400, we recorded a bogon-computron collision of the <jgorkos at gmail.com> flavor, containing:
> I'm using Xastir to test the AVRS/Locate server, and I'm having a hard time
> grasping the reply-acks concept.
> Here's a sample of the conversation:
> AB0OO>APX201,TCPIP*,qAC,T1FIFTH::LOCATE   :N5TEX-9{0a}7
> Sending ACK to AB0OO for MSG NUM 0a}7
> Thu Sep 27 06:58:25 PDT 2012:  AB0OO wants to know the location of 'N5TEX-9'
> Sending AVRS>APZ013,TCPIP*::AB0OO    :ack0a}7
> Thu Sep 27 06:58:25 PDT 2012:  Last position of N5TEX-9 at Tue Sep 25
> 16:41:44 PDT 2012 at 3609.17N/09555.35Wj
> lastHeard is Tue Sep 25 16:41:44 PDT 2012
> LOCATE>APZ013,TCPIP*::AB0OO    :N5TEX-9 heard 1d14h16m41s ago 3.91mi E of
> Tulsa, OK{8
> AB0OO>APX201,TCPIP*,qAC,T1FIFTH::LOCATE   :ack8{8
> 
> Briefly:  AB0OO using Xastir sends a message to "LOCATE" with the callsign
> of N5TEX-9.  The LOCATE server sees that, and acks immediately, so Xastir
> stops sending the request. Then the LOCATE server looks up the last known
> position for N5TEX-9, and sends a new message (with a new message number) to
> AB0OO.
> 
> So, Xastir is using the reply-acks format, as described here:
> www.aprs.org/aprs11/replyacks.txt
> The "message number" is "0a}7" when viewed from the original paradigm.   I
> attempt to send that ack to the Xastir client in the line that starts with
> "Sending ACK", but for some reason , Xastir ignores it.  Am I using the
> incorrect format for my ack?  Eventually (tomorrow, I hope), I'll implement
> the reply-acks algo, but I need this to work for ALL clients, regardless of
> whether they use the new paradigm or the old paradigm, so this testing is
> important.
> 
> Any thoughts?

I just spent some time looking at this (messaged you a few times).

When your LOCATE server sends an ack, it's sending it from the AVRS call-sign.

Looking through Xastir source, when Xastir receives an ack, it looks through
its message queue for a message to that callsign with that sequence number,
so I believe what is happening is that it has no messages in its outgoing
queue for AVRS, and doesn't do anything with it.

If your server replied with its callsign being the same as the one to which
xastir had directed a message (i.e., LOCATE instead of AVRS), then it would
probably recognize the ACK.

Xastir's sequence numbers are not globally unique, but unique per conversation.

I see you just replied to my message about that, so I'll end it here.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236        http://kevan.org/brain.cgi?DDTNM
"And, isn't sanity really just a one-trick pony anyway? I mean all you get is
 one trick, rational thinking, but when you're good and crazy, oooh, oooh,
 oooh, the sky is the limit!"  --- The Tick