{
{   The purpose of this request is to execute a command asynchronously in a
{ new task.  Any command other than a utility subcommand may be executed via
{ this request.
{
{   If the command being executed is not already packaged as a program, i.e.
{ it is an SCL procedure or built_in system command, an internal SCL program
{ is executed which in turn calls the command.  Otherwise, the command's own
{ program description is used.
{
{       CLP$EXECUTE_COMMAND (COMMAND, COMMAND_FILE, ENABLE_ECHOING, TASK_NAME,
{         TASK_ID, STATUS)
{
{ COMMAND: (input)  This parameter specifies the command to be executed.  The
{       text of this string must conform to the syntax of a single command.
{
{ COMMAND_FILE: (input)  This parameter specifies a file which becomes the
{       current command file (i.e.  $COMMAND) within the new task.  This
{       parameter is only meaningful if the command being executed is a
{       command utility, or for some other reason references the current
{       command file.  A null or blank string can be used to specify the
{       absence of a command file.
{
{ ENABLE_ECHOING: (input)  This  parameter determines whether the command may
{       be echoed (TRUE) or not (FALSE).
{
{ TASK_NAME: (input)  This parameter specifies the name to be used to refer to
{       the task subsequent to this request (e.g.  in a clp$get_task_status
{       request).
{
{ TASK_ID: (output)  This parameter specifies the identifier assigned to the
{       task and can be used in subsequent program management requests to
{       refer to the task.
{
{ STATUS: (output)  This parameter specifies the request status.
{
