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.. | ||
chuinit.c | ||
clkinit.c | ||
Makefile.tmpl | ||
README | ||
README.kern | ||
README.streams | ||
tty_chu_STREAMS.c | ||
tty_chu.c | ||
tty_clk_STREAMS.c | ||
tty_clk.c |
This directory contains code for two line disciplines which may work with BSD-style terminal drivers. While I'll try to cover installation details for the more useful one here as best I can, you really should know what you are doing before attempting to put one of these in your kernel since the details seem to vary from BSD variant to BSD variant. Tty_clk.c contains a generic clock support line discipline. The terminal driver is actually run in raw mode, giving you an eight bit data path. Instead of delivering the data character-by-character, however, the line discipline collects characters until one of two magic characters (your current erase and kill characters. Don't throw up) is received. A timestamp is then taken (by calling microtime()), inserted in the input buffer after the magic character, and the whole mess made available for input by the application. Both select() and SIGIO are supported by the discipline. Tty_chu.c is a special purpose line discipline for receiving the CHU time code. It understands enough about the format of the code CHU transmits to filter out errors, and delivers an entire ten character code group to the application all at once, including a timestamp for each character. The structure the code group is delivered in is defined in chudefs.h. Note that this line discipline is old and could use some rewriting for better portability. Please drop me a line if you are interested in using this. To install the clock line discipline, do something like the following: (1) Copy tty_clk.c into /sys/sys (2) Edit /sys/sys/tty_conf.c. You will want to include some facsimile of the following lines: #include "clk.h" #if NCLK > 0 int clkopen(), clkclose(), clkwrite(), clkinput(), clkioctl(); #endif #if NCLK > 0 { clkopen, clkclose, ttread, clkwrite, clkioctl, clkinput, nodev, nulldev, ttstart, nullmodem, /* 10- CLKLDISC */ ttselect }, #else { nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev }, #endif In Ultrix 4.2a and 4.3 the file to edit is /sys/data/tty_conf_data.c. The lines should be #if NCLK > 0 clkopen, clkclose, ttread, clkwrite, clkioctl, /* 10 */ clkinput, nodev, nulldev, ttstart, nulldev, #else nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, nodev, #endif Note that if your kernel doesn't include the ??select() entry in the structure (i.e. there are only 10 entry points in the structure) just leave it out. Also note that the number you give the line discipline (10 in my kernel) will be specific to your kernel and will depend on what is in there already. The entries sould be in order with no missing space; that is, if there are only seven disciplines already defined and you want to use 10 for good reason, you should define a dummy 9th entry like this nodev, nodev, nodev, nodev, nodev, /* 9 */ nodev, nodev, nodev, nodev, nodev, (3) Edit /sys/h/ioctl.h and include a line (somewhere near where other line disciplines are defined) like: #define CLKLDISC 10 /* clock line discipline */ The `10' should match what you used in /sys/sys/tty_conf.c. (4) Edit /sys/conf/files and add a line which looks like: sys/tty_clk.c optional clk (5) Edit the configuration file for the machine you want to use the clock line discipline on to include the following: pseudo-device clk 4 (6) Run config, then make clean, then make depend, then make vmunix. Then reboot the new kernel.