iomux_signal.h and wqueue.h should be usable in C++. Add

to IOMux doxygen group too.

include/ucore/wqueue.h

@@ -4,6 +4,17 @@
 #include "mbuf.h"
 #include "iomux.h"
 
+/** @addtogroup IOMux
+ *  @{ 
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Return code from users write callback
+ */
 enum UC_WQ_RESULT {
     /** INdicates the MBuf was fully processed and can be freed*/
     UC_WQ_DONE = 1,
@@ -51,15 +62,33 @@ typedef enum UC_WQ_RESULT (*wqueue_write_cb)(struct IOMux *mux, struct IOMuxFD *
  */
 typedef enum UC_WQ_RESULT (*wqueue_read_cb)(struct IOMux *mux, struct IOMuxFD *fd);
 
-/** Represents a queue of data to write.
+/** 
+ * Represents a queue of data to write.
+ * UCWQueue replaces a raw IOMuxFD, and manages a queue
+ * of data to write, held as a list of struct MBuf.
+ * See also uc_wqueue_init
+ *
  */
 struct UCWQueue {
+    /** Underlying IOMuxFD. This member needs to be registered
+     * with an IOMux, see the description of uc_wqueue_init
+     */
     struct IOMuxFD fd;
+    /** Linked list of struct MBuf
+     */
     struct TailQ queue;
+    /** Associated mux
+     */
     struct IOMux *mux;
+    /** Users callback for read events
+     */
     wqueue_read_cb read_cb;
+    /** Users callback for write events
+     */
     wqueue_write_cb write_cb;
 
+    /** Current number of queued struct MBuf
+     */
     unsigned int queue_len;
 };
 
@@ -120,4 +149,10 @@ int uc_wqueue_enqueue(struct UCWQueue *wqueue, struct MBuf *mbuf);
  */
 int uc_wqueue_flush(struct UCWQueue *wqueue);
 
+#ifdef __cplusplus
+}
+#endif
+
+/**  @} (addtogroup)*/
+
 #endif