+ /*
+ * (Based on the rand(3) manpage:)
+ *
+ * For each group of 10 bytes (or less), we do the following:
+ *
+ * Input into the hash function the top 10 bytes from the
+ * local 'md' (which is initialized from the global 'md'
+ * before any bytes are generated), the bytes that are
+ * to be overwritten by the random bytes, and bytes from the
+ * 'state' (incrementing looping index). From this digest output
+ * (which is kept in 'md'), the top (up to) 10 bytes are
+ * returned to the caller and the bottom (up to) 10 bytes are xored
+ * into the 'state'.
+ * Finally, after we have finished 'num' random bytes for the
+ * caller, 'count' (which is incremented) and the local and global 'md'
+ * are fed into the hash function and the results are kept in the
+ * global 'md'.
+ */
+