- * io_debug_complete - empty function called when conn is closing/waiting.
- * @conn: the connection.
+ * io_fd_block - helper to set an fd blocking/nonblocking.
+ * @fd: the file descriptor
+ * @block: true to set blocking, false to set non-blocking.
+ *
+ * Generally only fails is @fd isn't a valid file descriptor, otherwise
+ * returns true.
+ */
+bool io_fd_block(int fd, bool block);
+
+/**
+ * io_time_override - override the normal call for time.
+ * @nowfn: the function to call.
+ *
+ * io usually uses time_mono() internally, but this forces it
+ * to use your function (eg. for debugging). Returns the old
+ * one.
+ */
+struct timemono (*io_time_override(struct timemono (*now)(void)))(void);
+
+/**
+ * io_poll_override - override the normal call for poll.
+ * @pollfn: the function to call.