NetBSD's (kernel) init_main doesn't bother passing an explicit "-a"
flag to init. The code assumes that init will try an automatic
reboot (i.e., go multiuser) if invoked with no arguments.

Ultrix init, conversely (perversely?) assumes the default is "-s"
and only does an automatic reboot if the kernel explicitly passes
a "-a" argument.

The following patch to the NetBSD kernel causes init_main() to always
explicitly pass a "-s" or "-a" argument to init. This doesn't cost
much in space or time and I don't see how it can possibly hurt.  While
it's largely irrelevant to users with native NetBSD binaries it makes
NetBSD with Ultrix binaries much more palatable. I don't know if the
same applies to other vendor (or CSRG) versions of init.

*** sys/kern/init_main.c.DIST	Mon Jul 18 03:52:36 1994
--- sys/kern/init_main.c	Tue Aug 30 14:24:43 1994
***************
*** 359,364 ****
--- 359,368 ----
  			(void)subyte(--ucp, 's');
  			options = 1;
  		}
+ 		else {
+ 			(void) subyte(--ucp, 'a');
+ 			options = 1;
+ 		}
  #ifdef notyet
  		if (boothowto & RB_FASTBOOT) {
  			(void)subyte(--ucp, 'f');

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