handy.h: Clarify comment

diff --git a/handy.h b/handy.h
index 5347799..f75c900 100644 (file)
--- a/handy.h
+++ b/handy.h
@@ -260,8 +260,9 @@ typedef U64TYPE U64;
 
 #endif
 
-/* log(2) is pretty close to  0.30103, just in case anyone is grepping for it */
-#define BIT_DIGITS(N)   (((N)*146)/485 + 1)  /* log2(10) =~ 146/485 */
+/* log(2) (i.e., log base 10 of 2) is pretty close to 0.30103, just in case
+ * anyone is grepping for it */
+#define BIT_DIGITS(N)   (((N)*146)/485 + 1)  /* log10(2) =~ 146/485 */
 #define TYPE_DIGITS(T)  BIT_DIGITS(sizeof(T) * 8)
 #define TYPE_CHARS(T)   (TYPE_DIGITS(T) + 2) /* sign, NUL */