--- ray/src/gen/genprism.c	1991/11/12 17:04:46	2.1
+++ ray/src/gen/genprism.c	1993/08/02 14:23:04	2.4
@@ -16,10 +16,16 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  <stdio.h>
 
+#include  <math.h>
+
 #include  <ctype.h>
 
 #define  MAXVERT	1024		/* maximum # vertices */
 
+#ifdef  DCL_ATOF
+extern double  atof();
+#endif
+
 char  *pmtype;		/* material type */
 char  *pname;		/* name */
 
@@ -36,7 +42,6 @@ main(argc, argv)
 int  argc;
 char  **argv;
 {
-	double  atof();
 	int  an;
 	
 	if (argc < 4)