{
{   The purpose of this procedure is to wait for the arrival
{ of data on the given global socket. However, this indication
{ cannot be relied upon as the data may be delivered to the
{ next queued task waiting to receive data.
{
{       NLP$UDP_AWAIT_DATA_AVAILABLE (GLOBAL_SOCKET_ID, WAIT,
{             ACTIVITY_COMPLETE)
{
{ GLOBAL_SOCKET_ID: (input) This parameter specifies the global
{       socket identifier.
{
{ WAIT: (input) This parameter is set to TRUE if the caller is
{       willing to wait for the arrival of data.
{
{ ACTIVITY_COMPLETE: (output) This parameter is set to TRUE on the
{       arrival of data and when the current task is at the head of
{       the receive queue.
{
