{    This procedure processes the change_selection command.
{
{    The purpose of this command is to allow the user to change any of the
{ attributes of an existing record.  The record to be changed is identified by
{ the record parameter.  If one of the attributes to be changed is the record
{ name, this is done by specifying the new name in the new_record parameter.
{ In all other cases, the parameters have the same meaning as in the
{ add_selection command.
{
{ RECORD:  This is the name of the record the command is to change the
{       definition of.
{
{ NEW_RECORD:  Using this parameter causes the record name to be changed to the
{       value specified.  If this parameter is omitted, the name stays the
{       same.  Valid values for this parameter are SCL names.  All existing
{       references to the old name are changed to references to the new name.
{
{ STATISTIC:  This parameter has the same meaning as is described for the
{       add_selection command.
{
{    TIME :  This parameter has the same meaning as is described for the
{ add_selection command.
{
{ CONTINUOUS_DATE_TIME:  This parameter has the same meaning as is described
{       for the add_selection command.
{
{ DESCRIPTIVE_DATA:  This parameter has the same meaning as is described for
{       the add_selection command.
{
{ JOB_PREDECESSOR:  This parameter has the same meaning as is described for the
{       add_selection command.
{
{ TASK_PREDECESSOR:  This parameter has the same meaning as is described for
{       the add_selection command.
{
{ SYSTEM_JOB_NAME:  This parameter has the same meaning as is described for the
{       add_selection command.
{
{ GLOBAL_TASK_ID:  This parameter has the same meaning as is described for the
{       add_selection command.
{
{ STATUS: This parameter specifies the request status.
{       CONDITIONS:
{             pte$date_time_e1
{             pte$invalid_global_task_id
{             pte$redefined_selection
{             pte$task_id_index_out_of_range
{             pte$task_id_seqno_out_of_range
{             pte$undefined_selec_for_change
{             pte$undefined_selec_for_predec
