Problem reading from usb serial - bug?

[gdt]

I built RC-1.4.27 on a mac, using python from pkgsrc which used tk over x11, and ran it under xquartz. I connected it to an F9P over usb (ardusimple). That worked, functionally, but was slow, partly because that system is very old. I then built on NetBSD in a venv, using python 3.12. I connected the same receiver, and got nothing until I changed baud to 115200. I have a sky view, but nothing further. There are lots of errors in the console window about parsing failures.

I then fired up gpsd, and it read the stream fine, showing skyview with SNR, and position.

Looking at the errors, this jumped out at me:

WARNING>>Error parsing data stream Serial stream terminated unexpectedly. 1174 bytes requested, 872 bytes returned.

Example errors

WARNING>>Error parsing data stream Message checksum b'\x00\x00' invalid - should be b'\xf4\x93'
WARNING>>Error parsing data stream Unknown protocol header b'$\x00'.
WARNING>>Error parsing data stream Unknown protocol header b'$\x07'.
WARNING>>Error parsing data stream Unknown protocol header b'$\x02'.

Guessing a bit, there was a read system call asking for 1174, and 872 bytes were returned. That's allowable behavior under POSIX, and doesn't strike me as surprising for a device. I'll have a look at the code, but it seems like another read call should be issued.

[gdt]

Something else is going on; I am withdrawing this report for now.