#if !defined(lint) && defined(SCCSIDS)static	char sccsid[] = "@(#)signal.c 1.1 92/07/30 SMI"; /* from UCB 5.1 85/06/05 */#endif/* * Copyright (c) 1985 Regents of the University of California. * All rights reserved.  The Berkeley software License Agreement * specifies the terms and conditions for redistribution. *//* * Almost backwards compatible signal. */#include <signal.h>void (*signal(s, a))()	int s;	void (*a)();{	struct sigvec osv, sv;	static int mask[NSIG];	static int flags[NSIG];	sv.sv_handler = a;	sv.sv_mask = mask[s];	sv.sv_flags = flags[s];	if (sigvec(s, &sv, &osv) < 0)		return (BADSIG);	if (sv.sv_mask != osv.sv_mask || sv.sv_flags != osv.sv_flags) {		mask[s] = sv.sv_mask = osv.sv_mask;		flags[s] = sv.sv_flags = osv.sv_flags & ~SV_RESETHAND;		if (sigvec(s, &sv, (struct sigvec *)0) < 0)			return (BADSIG);	}	return (osv.sv_handler);}