1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #if defined(LIBC_SCCS) && !defined(lint) 9 static char sccsid[] = "@(#)frexp.c 8.1 (Berkeley) 06/04/93"; 10 #endif /* LIBC_SCCS and not lint */ 11 12 #include <sys/types.h> 13 #include <math.h> 14 15 double 16 frexp(value, eptr) 17 double value; 18 int *eptr; 19 { 20 union { 21 double v; 22 struct { 23 u_int u_mant1 : 7; 24 u_int u_exp : 8; 25 u_int u_sign : 1; 26 u_int u_mant2 : 16; 27 u_int u_mant3 : 32; 28 } s; 29 } u; 30 31 if (value) { 32 u.v = value; 33 *eptr = u.s.u_exp - 128; 34 u.s.u_exp = 128; 35 return(u.v); 36 } else { 37 *eptr = 0; 38 return((double)0); 39 } 40 } 41