2BSD/misc/access.sys

--- This is a new line for sysent.c ---
	2, &saccess,			/* 33 = access */
--- Also extern saccess at the beginning of sysent. ---
--- And this code should be placed at the end of sys2.c ---
/*
 * access system call
 */
saccess()
{
	extern uchar;
	register svuid, svgid;
	register *ip;

	svuid = u.u_uid;
	svgid = u.u_gid;
	u.u_uid = u.u_ruid;
	u.u_gid = u.u_rgid;
	ip = namei(&uchar, 0);
	if (ip != NULL) {
		if (u.u_arg[1]&(IREAD>>6))
			access(ip, IREAD);
		if (u.u_arg[1]&(IWRITE>>6))
			access(ip, IWRITE);
		if (u.u_arg[1]&(IEXEC>>6))
			access(ip, IEXEC);
		iput(ip);
	}
	u.u_uid = svuid;
	u.u_gid = svgid;
}
--- That should do it ---