+/** \fn void entropium_fillBlockRandom(void* block, unsigned length_B)
+ * \brief get a block of random data
+ *
+ * This function writes random data extracted from the entropy pool in the
+ * supplied buffer. It shares a internal buffer with the
+ * entropium_getRandomByte() function.
+ * \param block pointer to the buffer where the random data goes
+ * \param length_B number of bytes to be written to the buffer
+ */