diff --git a/extlib/benz/file.c b/extlib/benz/file.c
index 3a4f6228..888dbff0 100644
--- a/extlib/benz/file.c
+++ b/extlib/benz/file.c
@@ -353,24 +353,26 @@ int xvfprintf(pic_state *pic, xFILE *stream, const char *fmt, va_list ap) {
       break;
     }
 #else
+# define fabs(x) ((x) >= 0 ? (x) : -(x))
     case 'f': {
-      double dval, dint;
-      dval = modf(va_arg(ap, double), &dint);
-      if (dint < 0 || dval < 0) { /* either may be zero */
+      double dval = va_arg(ap, double);
+      long lval;
+      if (dval < 0) {
+        dval = -dval;
         xputc(pic, '-', stream);
         cnt++;
       }
-      cnt += print_int(pic, stream, (long)fabs(dint), 10);
+      lval = (long)dval;
+      cnt += print_int(pic, stream, lval, 10);
       xputc(pic, '.', stream);
       cnt++;
-      if ((ival = fabs(fabs(dval) * 1e4) + 0.5) == 0) {
+      dval -= lval;
+      if ((ival = fabs(dval) * 1e4 + 0.5) == 0) {
         cnt += xfputs(pic, "0000", stream);
       } else {
-        int i;
-        for (i = 0; i < 3 - (int)log10(ival); ++i) {
-          xputc(pic, '0', stream);
-          cnt++;
-        }
+        if (ival < 1000) xputc(pic, '0', stream); cnt++;
+        if (ival <  100) xputc(pic, '0', stream); cnt++;
+        if (ival <   10) xputc(pic, '0', stream); cnt++;
         cnt += print_int(pic, stream, ival, 10);
       }
       break;
diff --git a/extlib/benz/number.c b/extlib/benz/number.c
index bd723f9f..42f20640 100644
--- a/extlib/benz/number.c
+++ b/extlib/benz/number.c
@@ -117,11 +117,6 @@ DEFINE_AOP(div, pic_div(pic, pic_int_value(1), argv[0]), do {
     pic_errorf(pic, "/: at least one argument required");
   } while (0))
 
-/**
- * Returns the length of string representing val.
- * radix is between 2 and 36 (inclusive).
- * No error checks are performed in this function.
- */
 static int
 number_string_length(int val, int radix)
 {
@@ -141,12 +136,6 @@ number_string_length(int val, int radix)
   return count;
 }
 
-/**
- * Returns the string representing val.
- * radix is between 2 and 36 (inclusive).
- * This function overwrites buffer and stores the result.
- * No error checks are performed in this function. It is caller's responsibility to avoid buffer-overrun.
- */
 static void
 number_string(int val, int radix, int length, char *buffer) {
   const char digits[37] = "0123456789abcdefghijklmnopqrstuvwxyz";
@@ -216,7 +205,7 @@ pic_number_string_to_number(pic_state *pic)
   int radix = 10;
   long num;
   char *eptr;
-  double flo;
+  pic_value flo;
 
   pic_get_args(pic, "z|i", &str, &radix);
 
@@ -227,9 +216,9 @@ pic_number_string_to_number(pic_state *pic)
       : pic_float_value(num);
   }
 
-  flo = strtod(str, &eptr);
-  if (*eptr == '\0') {
-    return pic_float_value(flo);
+  flo = pic_read_cstr(pic, str);
+  if (pic_int_p(flo) || pic_float_p(flo)) {
+    return flo;
   }
 
   pic_errorf(pic, "invalid string given: %s", str);
diff --git a/extlib/benz/read.c b/extlib/benz/read.c
index 926204b2..6051ecf7 100644
--- a/extlib/benz/read.c
+++ b/extlib/benz/read.c
@@ -282,14 +282,18 @@ read_unsigned(pic_state *pic, struct pic_port *port, int c)
   }
 #else
   case '.': {
-    double f, g;
+    double f, g, h;
     next(pic, port);
     g = 0, e = 0;
     while (isdigit(c = peek(pic, port))) {
       g = g * 10 + (next(pic, port) - '0');
       e++;
     }
-    f = u + g * pow(10, -e);
+    h = 1.0;
+    while (e-- > 0) {
+      h /= 10;
+    }
+    f = u + g * h;
 
     exp = read_suffix(pic, port);
     if (exp >= 0) {