I needed the following patches to today's source (Wed) to get a kernel
to compile with slip and inet defined, but no ether defined. I just
went ahead and followed to style that icu.s used to do the same checks.

James

-- Cut Here --
*** nfs_vfsops.c+	Thu May 19 03:12:44 1994
--- nfs_vfsops.c	Thu May 19 03:13:29 1994
***************
*** 159,164 ****
--- 159,166 ----
   */
  nfs_mountroot()
  {
+ #include "ether.h"
+ #if NETHER > 0
  	register struct mount *mp;
  	register struct mbuf *m;
  	struct socket *so;
***************
*** 320,325 ****
--- 322,328 ----
  	rootvp = vp;
  	inittodr((time_t)0);	/* There is no time in the nfs fsstat so ?? */
  	return (0);
+ #endif
  }
  
  static void
*** in.c+	Wed May 18 23:17:28 1994
--- in.c	Thu May 19 03:10:59 1994
***************
*** 423,433 ****
  		ia->ia_addr = oldaddr;
  		return (error);
  	}
! 	if (ifp->if_output == ether_output) { /* XXX: Another Kludge */
  		ia->ia_ifa.ifa_rtrequest = arp_rtrequest;
  		ia->ia_ifa.ifa_flags |= RTF_CLONING;
  	}
! 	splx(s);
  	if (scrub) {
  		ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
  		in_ifscrub(ifp, ia);
--- 423,436 ----
  		ia->ia_addr = oldaddr;
  		return (error);
  	}
! #include "ether.h"
! #if NETHER > 0
!         if (ifp->if_output == ether_output) { /* XXX: Another Kludge */
  		ia->ia_ifa.ifa_rtrequest = arp_rtrequest;
  		ia->ia_ifa.ifa_flags |= RTF_CLONING;
  	}
! #endif
!         splx(s);
  	if (scrub) {
  		ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
  		in_ifscrub(ifp, ia);

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