Wed Nov 16 09:28:46 EST 2016

USB bus numbers not stable across boot

So how to make a persistent link to a physical usb serial port?  It
seems that only the serial number would work reliably.
EDIT: swiched to tty-<idvendor>-<idproduct>-<serialno>
tty-<usbpath> left as well, but it's not stable across boot on zoo