1 /* 2 * Copyright (c) 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This software was developed by the Computer Systems Engineering group 6 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 7 * contributed to Berkeley. 8 * 9 * %sccs.include.redist.c% 10 * 11 * from: $Header: isnan.c,v 1.1 91/07/08 19:03:34 torek Exp $ 12 */ 13 14 #if defined(LIBC_SCCS) && !defined(lint) 15 static char sccsid[] = "@(#)isnan.c 8.1 (Berkeley) 06/04/93"; 16 #endif /* LIBC_SCCS and not lint */ 17 18 #include <sys/types.h> 19 #include <machine/ieee.h> 20 21 isnan(d) 22 double d; 23 { 24 register struct ieee_double *p = (struct ieee_double *)&d; 25 26 return (p->dbl_exp == DBL_EXP_INFNAN && 27 (p->dbl_frach != 0 || p->dbl_fracl != 0)); 28 } 29