[avrdude-dev] jtag2 and usb timeout

[Dave N6NZ]

I have been chasing through the avrdude code, and down into libusb. For 
a while, I suspected my problem was related to a broken-looking test in 
libusb usb_bulk_read(). I updated libusb. The code for the old libusb on 
my system, and the 0.12 version that I updated to is *radically* 
different. But the results are the same.  So perhaps that was a red 
herring, but at least I now have an up-to-date libusb.

It really appears that libusb is returning an error status, without 
setting an error code.  Possibilities:
1) spurious error code for correct operation
2) missing error code for incorrect operation
3) Dave is too tired to be reading code and is totally lost.

I don't know enough about USB to find my way around in libusb, and the 
new version uses select() for threading, so of course it is complex.

-dave