I propose adding a typedef for the function type inside sysent.  Any
objects/comments/otherwise?  The trivial patch is appended.

/assar

Index: systm.h
===================================================================
RCS file: /cvsroot/syssrc/sys/sys/systm.h,v
retrieving revision 1.92
diff -u -w -r1.92 systm.h
--- systm.h     1999/06/26 08:25:26     1.92
+++ systm.h     1999/12/28 01:49:33
@@ -119,11 +119,12 @@
 struct tty;
 struct uio;

+typedef        int     sy_call_t __P((struct proc *, void *, register_t *));
+
 extern struct sysent {         /* system call table */
        short   sy_narg;        /* number of args */
        short   sy_argsize;     /* total size of arguments */
-                               /* implementing function */
-       int     (*sy_call) __P((struct proc *, void *, register_t *));
+       sy_call_t *sy_call;     /* implementing function */
 } sysent[];
 extern int nsysent;
 #if    BYTE_ORDER == BIG_ENDIAN