-int msnd_fifo_write(msnd_fifo *f, const char *buf, size_t len, int user);
-int msnd_fifo_read(msnd_fifo *f, char *buf, size_t len, int user);
+int msnd_fifo_write(msnd_fifo *f, const char *buf, size_t len);
+int msnd_fifo_read(msnd_fifo *f, char *buf, size_t len);