Packet queue strategy & data structure

Question

Hi all,
does anyone know an efficient data structure to implement a global packet queue in which packets from different connection are queued (by a thread) and removed by another thread ?
The basic idea is to have the following 2 threads (in pseudo code):
q is the global queue
// write thread
foreach (Connection c : connections) {
    Packet p = q.nextPacketToSendToThisConnection
    send as much bytes of p as the write() is a non-blocking operation
    if (p.bytesToSend == 0) {
        q.markPacketAsSendedForConnection(p, c)
// read thread (c is a Connection)
Packet p = c.readPacket()
q.queue(p)Thanks in advance

Answer 1

A simple queue using a linked list will do. Here's an example from some of my network code, the message is just a string, it could be something more complex. Attempts to avoid the synchronization are prone to error and may actually slow your code down.:
     LinkedList sendQ = new LinkedList();     // our transmission queue
     // the transmit queue
     // the transmit thread calls popMessage to get a string to send
     synchronized String popMessage()
          String msg = null;                                   // returns null if closed
          while (state > 0 && sendQ.size() == 0)          // wait until data or closed
               try{this.wait();}                              // wait relinguishes lock and lets other threads run
               catch(InterruptedException e){}               // ignore interrupts
          if(state > 0)msg = (String)sendQ.remove(0);     // we're open get oldest message form sendQ list
          return msg;
     // the client calls postMessage to put a string on the transmit queue
     synchronized void postMessage(String msg)
          sendQ.add(msg);               // append to transmit queue
          this.notify();               // tell popMessage to take a look
     }