timetag format

[trackme518]

Hi, I am not getting proper timetag with OSC bundle. Sender timetag differs to recieved timetag() extracted from OSC message.

Minimal code example:

import oscP5.*;
import netP5.*;

OscP5 oscP5;
NetAddress myRemoteLocation;

void setup() {
  size(400, 400);
  frameRate(60);
  oscP5 = new OscP5(this, 12000);
  myRemoteLocation = new NetAddress("127.0.0.1", 12000);
}


void draw() {
  background(0);
}


void mousePressed() {
  OscBundle myBundle = new OscBundle();
  OscMessage myMessage = new OscMessage("/test");
  myMessage.add("abc");
  myBundle.add(myMessage);

  long ts = System.currentTimeMillis();
  println("timetag send: "+  setTimetag(ts)+" millis: "+ts);
  myBundle.setTimetag( System.currentTimeMillis() );
  oscP5.send(myBundle, myRemoteLocation);
}



// incoming osc message are forwarded to the oscEvent method.
void oscEvent(OscMessage theOscMessage) {
  println("timetag recieved : "+ theOscMessage.timetag()  );
}

long setTimetag(long theTime) {
  final long secsSince1900 = theTime / 1000;
  final long secsFractional = ((theTime % 1000) << 32) / 1000;
  long l = (secsSince1900 << 32) | secsFractional;
  return l;
}

This produces:
When creating the OSC message:
timetag: 7231581490502040551 millis: 1683733773069

When the message is recieved:
timetag : -1727627929977226265

Why there is a negative sign? In what format is the timetag? Why is it not the same when setting it?

Can you clarify please? Thanks!