On 11/06/2014 06:53 PM, Tom Horsley wrote:
On Thu, 6 Nov 2014 18:47:23 -0500 Fred Smith wrote:
not finding anything on that, I hit on writing a udev rule for the USB device to make sure it appeared as a predictable /dev/video<x>.
Did you try looking in /dev/v4l? My laptop builtin webcam leaves entries in there. The v4l directory has 2 sub-directories: by-id and by-path which contain entries for my webcam.
I did something similar to recognize my 3D printer when I plug it in, and it was quite challenging to make all my code work because systemd runs things in magic "cgroups" that get killed quickly and have limited permissions. I eventually got all the complex stuff I wanted to do working. The full story is here:
http://home.comcast.net/~tomhorsley/hardware/solidoodle/solidoodle-udev.html