更新队列并从队列中删除所需的内容

Question

I am stuck in a really confusing situation here therefore, I am going to explain the whole scenario.

I have developed a UDP Server/ multiple Client appplication.

The Server has a main Receiving Thread. Each Client which wants to communicate with the Server first sends a Message with some ID to the Server. Server receives this Message from the Client. Server has a text file containing list of authorized IDs. When a Message is received from the client, server compares the ID received from the client with the IDs available in its text file. If client's ID matches with any ID in Server's text file, that client is considered as authenticated and a new thread alongwith a new socket is created dedicated for this client. The information of this new client is also updated in a Queue containing information of all active clients.

All this task is completed by now Now the issue is that since each client will have a dedicated thread serving it, I want these threads to send some message to their respective clients and wait for response from the client, if no response is received from the client within a specific time, the client is considered dead and is removed from the Queue in the main Receieving Thread.

But the problem is that how will "all" x number of clients will tell the main receieivng thread that their respective client is INACTIVE? If this part is done, will the main Receiving Thread have to traverse the whole Queue, find out the client's information which is dead and then how will this be deleted? this is really confusing situation for me.

It has been so long but I am unable to keep a recored of active clients in my application.

Please help me asap. Thanks in advance :)

EDIT: Another idea could be that the Queue has x number of elements and the satus of each client. eg: initially for x number of clients:

Client#    Status

1            0

2            0

3            0

.            .

.            .

.            .

.            .

x            0

Whenever a new Client becomes Active, Status is changed from 0 to 1 and whenever the client goes down, status is changed back form 1 to 0.

Does this seem to be correct approach?

Answer 1

I better advice you to use Tcp . Using UDP you are obliged to do things by yourself .

I want these threads to send some message to their respective clients and wait for response from the client

First: Make Queue or List thread safe

Pass the id (index) of the List where you storing information about client address ( client sockaddr) and other informations like state . Inside threadand use index to obtain info about client .obtaining client addr u can send message to it .

If this part is done, will the main Receiving Thread have to traverse the whole Queue, find out the client's information which is dead and then how will this be deleted? this is really confusing situation for me.

You will traverse list and obtain index of client and change state . in client thread when you will see that client state not changed to active within specific time you will delete that client info from list or queue.

Happy programmings