* \param length_B length of the key in bytes (between 1 and 255)
*/
-void arcfour_init(arcfour_ctx_t *ctx, void *key, uint8_t length_B);
+void arcfour_init(const void *key, uint8_t length_B, arcfour_ctx_t *ctx);
/** \fn uint8_t arcfour_gen(arcfour_ctx_t *ctx)
* \brief generates a byte of keystream