13  * 2006-05-12     Bernard      implement mailbox and message queue
19  * 2006-06-07     Bernard      fix the message queue send bug
33  * 2011-12-18     Bernard      add more parameter checking in message queue
70  * double-queue object (mailbox etc.) contains this kind of list.
126  * - remove the thread from suspend queue of IPC object
127  * - put the thread into system ready queue
1766  * This function will initialize a message queue and put it under control of
1770  * @param name the name of message queue
1774  * @param flag the flag of message queue
1829  * This function will detach a message queue object from resource management
1831  * @param mq the message queue object
1845     /* detach message queue object */  in rt_mq_detach()
1854  * This function will create a message queue object from system resource
1856  * @param name the name of message queue
1858  * @param max_msgs the maximum number of message in queue
1859  * @param flag the flag of message queue
1861  * @return the created message queue, RT_NULL on error happen
1885     /* init message queue */  in rt_mq_create()
1922  * This function will delete a message queue object and release the memory
1924  * @param mq the message queue object
1940     /* free message queue pool */  in rt_mq_delete()
1943     /* delete message queue object */  in rt_mq_delete()
1952  * This function will send a message to message queue object, if there are
1953  * threads suspended on message queue object, it will be waked up.
1955  * @param mq the message queue object
1983     /* message queue is full */  in rt_mq_send()
2004     /* link msg to message queue */  in rt_mq_send()
2041  * This function will send an urgent message to message queue object, which
2042  * means the message will be inserted to the head of message queue. If there
2043  * are threads suspended on message queue object, it will be waked up.
2045  * @param mq the message queue object
2073     /* message queue is full */  in rt_mq_urgent()
2093     /* link msg to the beginning of message queue */  in rt_mq_urgent()
2125  * This function will receive a message from message queue object, if there is
2126  * no message in message queue object, the thread shall wait for a specified
2129  * @param mq the message queue object
2169     /* message queue is empty */  in rt_mq_recv()
2235     /* get message from queue */  in rt_mq_recv()
2238     /* move message queue head */  in rt_mq_recv()
2240     /* reach queue tail, set to NULL */  in rt_mq_recv()
2268  * This function can get or set some extra attributions of a message queue
2271  * @param mq the message queue object
2294         /* release all message in the queue */  in rt_mq_control()
2297             /* get message from queue */  in rt_mq_control()
2300             /* move message queue head */  in rt_mq_control()
2302             /* reach queue tail, set to NULL */  in rt_mq_control()