{
{ The purpose of this request is to update an array of iostatus variables of
{ previously initiated MMP$READ AND MMP$WRITE requests.  The
{ MMP$CHECK_IO_STATUS updates all iostatus variables that were not
{ previously updated as complete.  The user may specify that the calling
{ task wait a specified amount of time if no input or output requests
{ have completed.  A call to this procedure cannot come from above ring 6.
{
{      MMP$CHECK_IO_STATUS (STATUS_POINTER_ARRAY, WAIT_TIME, INDEX,
{         STATUS)
{
{
{  STATUS_POINTER_ARRAY: (input) This parameter specifies an array of
{      pointers to iostatus variables to be checked. NIL pointers in
{      this array are acceptable and indicate an empty position in
{      the array.
{
{  WAIT_TIME: (input) This parameter specifies the maximum amount of
{      time to wait for an IO completion if no iostatus variables have
{      io-complete status set.  If the value of this parameter is zero
{      then no wait will be done and control will be returned
{      immediately. The wait_time is specified in milliseconds.
{
{  INDEX: (output) This parameter specifies the index of the first
{      iostatus in the status_pointer_array that has io complete.
{      The value of this parameter is set to zero if no io has
{      completed.
{
{  STATUS: (output) This parameter specifies the request status.
{       Possible error codes are:
{         mme$nil_io_control_block (attempt to check the status of a
{           request when no asynchronous requests have been issued)
{         mme$invalid_io_status_ptrs (attempt to check the status of a
{           request and wait for completion using a pointer to a status
{           variable that has not been used for an asynchronous request)
{         error codes for mmp$read
{         error codes for mmp$write
{
