-/* Initializes B to be a bitmap of BIT_CNT bits
- and sets all of its bits to false.
- Returns true if success, false if memory allocation
- failed. */
+/* Creates and returns a pointer to a newly allocated bitmap with room for
+ BIT_CNT (or more) bits. Returns a null pointer if memory allocation fails.
+ The caller is responsible for freeing the bitmap, with bitmap_destroy(),
+ when it is no longer needed. */