rhb@bu-pub.bu.edu (Rick Broberg) (01/23/91)
I'm trying to read from a /dev/tty in ultrix which is the external serial port on the machine. I can open it, ioctl it for proper speed and data format configuration, even write to it just fine. When I read from it, read *never* blocks, and multiple reads return the same thing over and over, including some random junk. Read doesn't return -1 or 0, just random numbers. Do I need to write a device driver for this? If so, how? Can I escape having to? If I must, why is it that the output to the port does work but not the input.