--- ray/src/cv/thf2rad.c	1991/12/19 15:05:54	2.2
+++ ray/src/cv/thf2rad.c	1993/08/02 14:08:55	2.4
@@ -13,19 +13,20 @@ static char SCCSid[] = "$SunId$ LBL";
  */
 
 #include <stdio.h>
+#include <math.h>
 
 #define MAXSTR		128		/* maximum string or id length */
 #define MAXPTS		2048		/* maximum points per object */
 
-#ifndef atof
-extern double  atof();
-#endif
-
 typedef struct {
 	double	x, y, z;
 } POINT;
 
 double	rad = 0.0;			/* line radius */
+
+#ifdef  DECL_ATOF
+extern double  atof();
+#endif
 
 
 main(argc, argv)