(******************************************************************************
*                              1                                              *
*                                                                             *
*  Purpose :                                                                  *
*                                                                             *
*    Input :                                                                  *
*                                                                             *
*    Output:                                                                  *
*                                                                             *
*  External constants :              =                         ;              *
*                                                                             *
*  External types     :              =                         ;              *
*                                                                             *
*  External variables :              =                         ;              *
*                                                                             *
*  External procedures:              =                         ;              *
*                                                                             *
*  Pre-condition :                                                            *
*                                                                             *
*  Post-condition:                                                            *
*                                                                             *
*    Notes :                                                                  *
*                                                                             *
*   Errors : 0:                                                               *
*            1:                                                               *
*                                                                             *
*           Version Date : 29/04/91                                           *
******************************************************************************)