- Replace references to linesw[0] with a ttyldisc_default() function
that returns the default ("termios") line discipline.
- The linesw[] array is gone, replaced by a linked list.
- ttyldisc_add() and ttyldisc_remove() have been replaced by
ttyldisc_attach() and ttyldisc_detach().
- Things that provide line disciplines are now responsible for
registering those disciplines with the system. The linesw
structures are no longer declared in tty_conf.c
- Line disciplines are now refcounted; a lookup causes a reference to
be held. ttyldisc_release() releases the reference. Attempts to
detach an in-use line discipline result in EBUSY.
- Fix function signature lossage in if_sl.c, if_strip.c, and tty_tb.c
that was masked by the old tty_conf.c
- tty_init() is no longer necessary; delete it and its call from main().
7d00e1aff3