Good evening,
I've made a small test to see if it's possible to inject some GPS data inside an SER video.
I'm using a Raspberry Pi 4 with StellarMate OS a GPS dongle (configured as Jasem Mutlaq said in his video) and my ASI 174mm-cool as a video source.
I've tried to alter the date/time inside the StellarMate OS and my main OS (Windows 10), but the SER recordings are saved with the altered (StellarMate OS one) date/time, not from the GPS date/time.
To start the recording I've used my main OS with Ekos, but the SER is saved on an HDD attached to the Raspberry Pi because it's not possible to save it from the Raspberry to the Windows 10 machine.
What am I doing wrong?
Should I start the recording from the Raspberry Pi directly?

Thanks a lot in advance!

Best regards
Giacomo

It is already recorded in StellarMate, so your only issue is the timestamp. If a GPS dongle is plugged in, then SM should sync with the GPS time on boot up. You can inspect the StellarMate Device Manager log (SM Dashboard --> Logs --> Device Manager) and see that it syncs the GPS. If it fails to do so, it will note that in the log.

First of all, thanks for the reply.
Probably I've explained myself not in a good way, my bad.
I wish to inject the GPS time inside the SER timestamp.
The overall system works, StellarMate catches the proper time (via NTP and/or GPS) and the GPS is fixed (gpsmon or from the INDI panel I can see the proper time). But for testing, I've altered the system time to see if the GPS time is injected in the SER video and that's not the case.
I wished to make so for the occultations, so I can have a quite precise timing like with a Watec camera or the new QHY camera with GPS.
But even if in KStars is set to "fetch the date/time from GPS", as soon as I record a SER file, I see the system (altered) time.
And I don't know if I misunderstood something about the GPS driver, or if there is something wrong with the things I'm doing.
This time, for testing, I've done everything inside StellarMate OS (via VNC).

I hope to have explained a little bit better everything !

Thanks a lot again for everything you do Jasem !

Best regards
Giacomo

Just because I wished to understand a bit more how the GPSD driver works, I've done a quick dig inside the code and I've noticed the setSystemTime function that should handle all the time update processes:
But, according to the man page linux.die.net/man/2/stime it only works as superuser.
So to let it work properly, the INDI server must be executed as root?

I'm struggling a bit with my memories of POSIX programming here .
Something that I have to refresh .

Thanks a lot again!

Yes it should work in StellarMate to it's configured to set time from a regular user as well. Furthermore, what I meant is that after bootup and even before INDI GPS driver is running, the system should sync itself with the GPS already.