I believe an exception in the case is defined by the device driver.
I don't think anyone has implemented it with the possible exception (no pun
intended) of network driver that send SIGURG on OOB data.
Brian Atkins ...{attunix, hao, allegra, ucbvax}!nbires!atkins
NBI Inc., P.O. Box 9001, Boulder CO 80301 (303) 444-5710