Add doxygen groups

include/ucore/iomux.h

@@ -2,7 +2,18 @@
 #define IO_MUX_H_
 
 #include "timers.h"
-
+/** @addtogroup IOMux
+ *  @{ 
+ *  The IOMux is an I/O multiplexer, implementing a main eventloop.
+ *  The event loop can be used to register callbacks for activity on
+ *  file descriptors such as sockets and pips, and for timers.
+ *  
+ *  The IOMux is backed either by the select() system call, or the epoll
+ *  facility on Linux. Several IOMuxes can run in different threads concurrently,
+ *  but note that the IOMux itself is not thread safe so operations in one thread
+ *  cannot work on an IOMux running in another thread.
+ *
+ *  */
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -22,9 +33,20 @@ enum IOMUX_TYPE {
     IOMUX_TYPE_EPOLL
 };
 
-/** Opaque struct */
+/** The IOMux used to issue mux operations. This is to be treated as an opaque
+ *  handle. Use  iomux_create() or iomux_create_ex() to create an IOMux, register
+ *  callbakcs, and call iomux_run() to process the events
+ */
 struct IOMux;
+
 struct IOMuxFD;
+
+/** Callback function used in struct IOMuxFD
+ * @param mux the mux that issued the callback.
+ * @param fd the file desciptor structure.
+ * @param event A bitmask of the MUX_EV_XX values. Both a read and a write event
+ *        might be signalled in the same callback
+ */
 typedef void (*iomux_cb)(struct IOMux *mux, struct IOMuxFD *fd, unsigned int event);
 
 /** Represents a watched file descriptor */
@@ -76,7 +98,10 @@ int iomux_run(struct IOMux *mux);
  */
 int iomux_register_fd(struct IOMux *mux, struct IOMuxFD *fd);
 
-/** Removes the file descriptor*/
+/** Removes the file descriptor
+ *
+ * @return 0 on success, an errno value on error
+ */
 int iomux_unregister_fd(struct IOMux *mux, struct IOMuxFD *fd);
 
 /** Updates the events to watch for in fd->what
@@ -120,5 +145,6 @@ struct UCTimers *iomux_get_timers(struct IOMux *mux);
 }
 #endif
 
+/**  @} (addtogroup)*/
 #endif