Add cross-references to rfork(2).

lib/libc/sys/fork.2

@@ -114,6 +114,7 @@ There is insufficient swap space for the new process.
 .El
 .Sh SEE ALSO
 .Xr execve 2 ,
+.Xr rfork 2 ,
 .Xr vfork 2 ,
 .Xr wait 2
 .Sh HISTORY

lib/libc/sys/vfork.2

@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     @(#)vfork.2	8.1 (Berkeley) 6/4/93
-.\"	$Id$
+.\"	$Id: vfork.2,v 1.8 1997/02/22 15:04:34 peter Exp $
 .\"
 .Dd June 4, 1993
 .Dt VFORK 2
@@ -92,6 +92,7 @@ since buffered data would then be flushed twice.)
 .Sh SEE ALSO
 .Xr execve 2 ,
 .Xr fork 2 ,
+.Xr rfork 2 ,
 .Xr sigvec 2 ,
 .Xr wait 2
 .Sh RETURN VALUES