I want to modify the temperature sample from simplicity so that I will be able to send messages from ED to AP.

ED is the one establishing the connection.

In AP I have

// Wait for the Join semaphore to be set by the receipt of a Join frame from a
// device that supports and End Device.

if (sJoinSem && (sNumCurrentPeers < NUM_CONNECTIONS))
{
// listen for a new connection
SMPL_LinkListen(&sLID[sNumCurrentPeers]);
sNumCurrentPeers++;
BSP_ENTER_CRITICAL_SECTION(intState);
if (sJoinSem)
{
sJoinSem--;
}
BSP_EXIT_CRITICAL_SECTION(intState);
}

if connection is established how can I get ED's linkID to be able to send messages to it?