This is a set of patches to the serial driver in 0.99pl14. It contains the following fixes / improvements: * Set FIFO trigger level to 1 if baud rate is under 2400. This will improve response time on 16550A's when they are operating at slow speeds; specifically when you're using them with a mouse. * Overrun conditions are now passed up to tty_io.c, and an appropriate warning message is printed. (Previously, tty_io.c would handle it as a randomly as either a frame error, a parity error, or a break.) * Use a separate flag for hardware flow control, so that the right thing happens when both XON/XOFF and RTS/CTS flow control are enabled. * Allow the callout devices to be a controlling tty. * Hangup handling fixed; some race conditions removed. The device specific close now happens at the instant when the hangup is signaled, instead of waiting until the the process closed the file descriptor. This should fix the problems with background processes that still have the tty opened when the modem hangs up. Linux will now deal correctly with this case. Please try these changes out, especially if you support dialup via modems. There are a bunch of tricky race conditions with the hangup code, which I *think* that I've resolved. I want to make sure that they work, though, before submitting them to Linux for inclusion in the mainline kernel. Please try them out and let me know how they work on your system. Ted Ts'o tytso@mit.edu 12/8/93