I have a USB to serial converter attached to my box. pl2303: Prolific
PL2303 USB to serial adaptor driver
if I login to the box and send/receive serial commands over this unit it
works without error EVERY time. however, if I run the same command set from with-in the extensions.conf
I get errors in dmesg like "pl2303 ttyUSB0: pl2303_open - failed
submitting read urb, error -22"
and then obviusly my command does not work. however, again - If I go back to the command line and my command it runs