{    The purpose of this request is to establish a condition handler for the
{ block exit condition.
{
{    Only one condition handler may be established in a procedure block with
{ this request.  This request is not compatible with the
{ pmp$establish_condition_handler request.  If this request is made multiple
{ times, the last request holds.
{
{    Each time this request is called the stack grows by several bytes so do
{ not use this request in a loop.
{
{       OSP$ESTABLISH_BLOCK_EXIT_HNDLR (CONDITION_HANDLER);
{
{ CONDITION_HANDLER: (input)  This is the condition handling procedure that is
{       to be given control in the current block.
