+/* Returns the number of chars needed to format variables of the
+ * specified type as a decimal string. Adds in extra space for a
+ * negative '-' prefix. */
+
+#define DECIMAL_STR_MAX(type) \
+ (1+(sizeof(type) <= 1 ? 3 : \
+ sizeof(type) <= 2 ? 5 : \
+ sizeof(type) <= 4 ? 10 : \
+ sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
+