i finally felt brave enough to try and work out what
the hell needed to be done for this, and so i did.

included below is the patch to sys/arch/sparc/dev/zs.c
to add the TIOCSBRK and TIOCCBRK ioclt's ..

i may look in to implimenting the few remaining ioctls
that aren't handled ...



*** zs.c.orig	Thu Mar 24 20:57:07 1994
--- zs.c	Fri May 13 21:55:28 1994
***************
*** 961,967 ****
  	int unit = minor(dev);
  	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
  	register struct tty *tp = zi->zi_cs[unit & 1].cs_ttyp;
! 	register int error;
  
  	error = linesw[tp->t_line].l_ioctl(tp, cmd, data, flag, p);
  	if (error >= 0)
--- 961,968 ----
  	int unit = minor(dev);
  	struct zsinfo *zi = zscd.cd_devs[unit >> 1];
  	register struct tty *tp = zi->zi_cs[unit & 1].cs_ttyp;
! 	register int error, s;
! 	register struct zs_chanstate *cs = &zi->zi_cs[unit & 1];
  
  	error = linesw[tp->t_line].l_ioctl(tp, cmd, data, flag, p);
  	if (error >= 0)
***************
*** 973,981 ****
  	switch (cmd) {
  
  	case TIOCSBRK:
! 		/* FINISH ME ... need implicit TIOCCBRK in zsclose as well */
  
  	case TIOCCBRK:
  
  	case TIOCSDTR:
  
--- 974,997 ----
  	switch (cmd) {
  
  	case TIOCSBRK:
! 		{
! 			s = splzs();
! 			cs->cs_preg[5] |= ZSWR5_BREAK;
! 			cs->cs_creg[5] |= ZSWR5_BREAK;
! 			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
! 			splx(s);
! 			break;
! 		}
  
  	case TIOCCBRK:
+ 		{
+ 			s = splzs();
+ 			cs->cs_preg[5] &= ~ZSWR5_BREAK;
+ 			cs->cs_creg[5] &= ~ZSWR5_BREAK;
+ 			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
+ 			splx(s);
+ 			break;
+ 		}
  
  	case TIOCSDTR:
  

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