--- ray/src/rt/func.c	2016/03/22 03:56:17	2.31
+++ ray/src/rt/func.c	2016/04/27 21:11:32	2.32
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: func.c,v 2.31 2016/03/22 03:56:17 greg Exp $";
+static const char	RCSid[] = "$Id: func.c,v 2.32 2016/04/27 21:11:32 greg Exp $";
 #endif
 /*
  *  func.c - interface to calcomp functions.
@@ -37,7 +37,7 @@ static double  l_erf(char *), l_erfc(char *), l_arg(ch
 
 
 void
-initfunc()	/* initialize function evaluation */
+initfunc(void)	/* initialize function evaluation */
 {
 	if (!rayinitcal[0])	/* already done? */
 		return;
@@ -67,16 +67,30 @@ initfunc()	/* initialize function evaluation */
 void
 set_eparams(char *prms)
 {
-	static char	*last_params = NULL;
+	static char	*last_params;
+	static int	lplen = 0;
+	int		len;
 	char		vname[RMAXWORD];
 	double		value;
 	char		*cpd;
 					/* check if already set */
-	if ((prms == NULL) | (prms == last_params))
+	if (prms == NULL || !*prms)
 		return;
-	if (last_params != NULL && !strcmp(prms, last_params))
+	if (lplen && !strcmp(prms, last_params))
 		return;
-	last_params = prms;		/* assign each variable */
+	len = strlen(prms);		/* record new settings */
+	if ((lplen != 0) & (lplen <= len)) {
+		free(last_params);
+		lplen = 0;
+	}
+	if (!lplen) {
+		lplen = len + 100;
+		last_params = (char *)malloc(lplen);
+		if (last_params == NULL)
+			error(SYSTEM, "out of memory in set_eparams()");
+	}
+	strcpy(last_params, prms);
+					/* assign each variable */
 	while (*prms) {
 		if (isspace(*prms)) {
 			++prms; continue;