--- ray/src/common/portio.c	2003/02/25 02:47:21	2.7
+++ ray/src/common/portio.c	2005/02/18 16:34:27	2.12
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: portio.c,v 2.7 2003/02/25 02:47:21 greg Exp $";
+static const char	RCSid[] = "$Id: portio.c,v 2.12 2005/02/18 16:34:27 greg Exp $";
 #endif
 /*
  * Portable i/o for binary files
@@ -11,12 +11,16 @@ static const char	RCSid[] = "$Id: portio.c,v 2.7 2003/
 
 #include <stdio.h>
 
-#ifndef frexp
-extern double  frexp();
+#include "rtio.h"
+
+#include <math.h>
+
+#ifdef getc_unlocked		/* avoid horrendous overhead of flockfile */
+#undef getc
+#undef putc
+#define getc    getc_unlocked
+#define putc    putc_unlocked
 #endif
-#ifndef ldexp
-extern double  ldexp();
-#endif
 
 
 void
@@ -99,6 +103,10 @@ FILE  *fp;
 	double	d;
 
 	l = getint(4, fp);
+	if (l == 0) {
+		getc(fp);		/* exactly zero -- ignore exponent */
+		return(0.0);
+	}
 	d = (l + (l > 0 ? .5 : -.5)) * (1./0x7fffffff);
 	return(ldexp(d, (int)getint(1, fp)));
 }