! *** PREDECLARED TYPES
     
      %IF %DECLARED ( %BASIC$QUADWORD_DECLARED ) = 0 %THEN
         RECORD BASIC$QUADWORD
            LONG FILL ( 2 )
         END RECORD
         %LET %BASIC$QUADWORD_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$OCTAWORD_DECLARED ) = 0 %THEN
         RECORD BASIC$OCTAWORD
            LONG FILL ( 4 )
         END RECORD
         %LET %BASIC$OCTAWORD_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$HFLOAT_AXP_DECLARED ) = 0 %THEN
         RECORD BASIC$HFLOAT_AXP
            LONG FILL ( 4 )
         END RECORD
         %LET %BASIC$HFLOAT_AXP_DECLARED = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$F_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$F_FLOATING_COMPLEX
            SINGLE REAL_PART
            SINGLE IMAGINARY_PART
         END RECORD
         %LET %BASIC$F_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$D_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$D_FLOATING_COMPLEX
            DOUBLE REAL_PART
            DOUBLE IMAGINARY_PART
         END RECORD
         %LET %BASIC$D_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$G_FLOATING_COMPLEX_DECL ) = 0 %THEN
         RECORD BASIC$G_FLOATING_COMPLEX
            GFLOAT REAL_PART
            GFLOAT IMAGINARY_PART
         END RECORD
         %LET %BASIC$G_FLOATING_COMPLEX_DECL = 1
      %END %IF
     
      %IF %DECLARED ( %BASIC$H_FLOAT_AXP_CMPLX_DCL ) = 0 %THEN
         RECORD BASIC$H_FLOATING_COMPLEX_AXP
            BASIC$HFLOAT_AXP REAL_PART
            BASIC$HFLOAT_AXP IMAGINARY_PART
         END RECORD
         %LET %BASIC$H_FLOAT_AXP_CMPLX_DCL = 1
      %END %IF
    
    
      DECLARE LONG CONSTANT OPC$_RQ_TERME = 1  !  ENABLE TERMINAL 
      DECLARE LONG CONSTANT OPC$_RQ_LOGI = 2  !  INITIALIZE THE LOG 
      DECLARE LONG CONSTANT OPC$_RQ_RQST = 3  !  OPERATOR REQUEST 
      DECLARE LONG CONSTANT OPC$_RQ_REPLY = 4  !  OPERATOR REPLY 
      DECLARE LONG CONSTANT OPC$_RQ_CANCEL = 5  !  CANCEL REQUEST 
      DECLARE LONG CONSTANT OPC$_RQ_STATUS = 6  !  REQUEST OPERATOR STATUS 
      DECLARE LONG CONSTANT OPC$_RQ_SECURITY = 7  !  MESSAGE TO SECURITY OPERATOR
      DECLARE LONG CONSTANT OPC$_RQ_LICENSE = 8  !  MESSAGE TO LICENSE OPERATOR
      DECLARE LONG CONSTANT OPC$M_RQ_NOOCS = 128
      DECLARE LONG CONSTANT OPC$M_NM_CENTRL = x'00000001'
      DECLARE LONG CONSTANT OPC$M_NM_PRINT = x'00000002'
      DECLARE LONG CONSTANT OPC$M_NM_TAPES = x'00000004'
      DECLARE LONG CONSTANT OPC$M_NM_DISKS = x'00000008'
      DECLARE LONG CONSTANT OPC$M_NM_DEVICE = x'00000010'
      DECLARE LONG CONSTANT OPC$M_NM_CARDS = x'00000020'
      DECLARE LONG CONSTANT OPC$M_NM_NTWORK = x'00000040'
      DECLARE LONG CONSTANT OPC$M_NM_CLUSTER = x'00000080'
      DECLARE LONG CONSTANT OPC$M_NM_SECURITY = x'00000100'
      DECLARE LONG CONSTANT OPC$M_NM_REPLY = x'00000200'
      DECLARE LONG CONSTANT OPC$M_NM_SOFTWARE = x'00000400'
      DECLARE LONG CONSTANT OPC$M_NM_LICENSE = x'00000800'
      DECLARE LONG CONSTANT OPC$M_NM_OPER1 = x'00001000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER2 = x'00002000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER3 = x'00004000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER4 = x'00008000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER5 = x'00010000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER6 = x'00020000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER7 = x'00040000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER8 = x'00080000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER9 = x'00100000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER10 = x'00200000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER11 = x'00400000'
      DECLARE LONG CONSTANT OPC$M_NM_OPER12 = x'00800000'
      DECLARE LONG CONSTANT OPC$S_OPCDEF = 158
      record OPCDEF
         BYTE OPC$B_MS_TYPE                 !  MESSAGE TYPE 
         group OPC$R_MS_C_T_S_OVERLAY       !  Class-Target-Status
            variant
               case
                  group OPC$R_MS_TARG_STAT_OVERLAY
                     group OPC$R_MS_TARGET_OVERLAY
                        variant
                        case
                           BYTE OPC$B_MS_TARGET  !  MESSAGE TARGET
                        case
                           BYTE OPC$B_MS_ENAB  !  MESSAGE ENABLES
                        end variant
                     end group OPC$R_MS_TARGET_OVERLAY
                     WORD OPC$W_MS_STATUS   !  MESSAGE STATUS
                  end group OPC$R_MS_TARG_STAT_OVERLAY
               case
                  BYTE OPC$Z_MS_TARGET_CLASSES ( 1 to 3 )
               case
                  BYTE OPC$Z_MS_ENAB_TERMINALS ( 1 to 3 )
            end variant
         end group OPC$R_MS_C_T_S_OVERLAY
         group OPC$R_MS_RPLYID_OVERLAY
            variant
               case
                  LONG OPC$L_MS_RPLYID      !  REPLY ID 
               case
                  group OPC$R_MS_MASK_OVERLAY
                     variant
                     case
                        LONG OPC$L_MS_MASK  !  MESSAGE MASK 
                     case
                        LONG OPC$L_MS_RQSTID  !  REQUEST ID 
                     end variant
                  end group OPC$R_MS_MASK_OVERLAY
            end variant
         end group OPC$R_MS_RPLYID_OVERLAY
         group OPC$R_MS_TEXT_OVERLAY
            variant
               case
                  LONG OPC$L_MS_TEXT        !  MESSAGE TEXT 
               case
                  group OPC$R_MS_TEXT_FIELDS
                     WORD OPC$W_MS_OUNIT    !  OPERATOR UNIT NUMBER 
                     STRING OPC$T_MS_ONAME = 1  !  OPERATOR NAME 
                  end group OPC$R_MS_TEXT_FIELDS
            end variant
         end group OPC$R_MS_TEXT_OVERLAY
         WORD OPCDEF$$_FILL_1 ( 1 to 7 )       !  SPACE FOR NAME 
         LONG OPC$L_MS_OTEXT ( 1 to 32 )       !  OPERATOR TEXT 
         group OPC$R_MS_MAXSZ_OVERLAY
            variant
               case
                  LONG OPC$L_MS_MAXSZ       !  MESSAGE MAX SIZE 
    !  OPERATOR MESSAGE TYPES 
               case
                  group OPC$R_MS_MAXSZ_BITS
                     LONG NM_CENTRL_bits   ! COMMENT ADDED BY SDL - NM_CENTRL_bits contains bits NM_CENTRL through NM_OPER12
                  end group OPC$R_MS_MAXSZ_BITS
            end variant
         end group OPC$R_MS_MAXSZ_OVERLAY
      end record OPCDEF
    
      DECLARE LONG CONSTANT OPC$M_OPR_CENTRAL = x'00000001'
      DECLARE LONG CONSTANT OPC$M_OPR_PRINTER = x'00000002'
      DECLARE LONG CONSTANT OPC$M_OPR_TAPES = x'00000004'
      DECLARE LONG CONSTANT OPC$M_OPR_DISKS = x'00000008'
      DECLARE LONG CONSTANT OPC$M_OPR_DEVICES = x'00000010'
      DECLARE LONG CONSTANT OPC$M_OPR_CARDS = x'00000020'
      DECLARE LONG CONSTANT OPC$M_OPR_NETWORK = x'00000040'
      DECLARE LONG CONSTANT OPC$M_OPR_CLUSTER = x'00000080'
      DECLARE LONG CONSTANT OPC$M_OPR_SECURITY = x'00000100'
      DECLARE LONG CONSTANT OPC$M_OPR_REPLY = x'00000200'
      DECLARE LONG CONSTANT OPC$M_OPR_SOFTWARE = x'00000400'
      DECLARE LONG CONSTANT OPC$M_OPR_LICENSE = x'00000800'
      DECLARE LONG CONSTANT OPC$M_OPR_USER1 = x'00001000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER2 = x'00002000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER3 = x'00004000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER4 = x'00008000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER5 = x'00010000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER6 = x'00020000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER7 = x'00040000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER8 = x'00080000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER9 = x'00100000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER10 = x'00200000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER11 = x'00400000'
      DECLARE LONG CONSTANT OPC$M_OPR_USER12 = x'00800000'
      DECLARE LONG CONSTANT OPC$S_OPC_OPRDEF = 3
      record OPC_OPRDEF
         variant
            case
               group OPC$R_OPRDEF_BITS
                  LONG OPR_CENTRAL_bits   ! COMMENT ADDED BY SDL - OPR_CENTRAL_bits contains bits OPR_CENTRAL through OPR_USER12
               end group OPC$R_OPRDEF_BITS
         end variant
      end record OPC_OPRDEF
    
      DECLARE LONG CONSTANT OPC$K_SYSTEM = 1
      DECLARE LONG CONSTANT OPC$K_GROUP = 2
      DECLARE LONG CONSTANT OPC$K_USER = 3
      DECLARE LONG CONSTANT OPC$K_UNSPEC = 4
      DECLARE LONG CONSTANT OPC$C_SYSTEM = 1
      DECLARE LONG CONSTANT OPC$C_GROUP = 2
      DECLARE LONG CONSTANT OPC$C_USER = 3
      DECLARE LONG CONSTANT OPC$C_UNSPEC = 4
      DECLARE LONG CONSTANT OPC$K_SW_VERSION = 9
      DECLARE LONG CONSTANT OPC$K_MAXREAD = 2560
      DECLARE LONG CONSTANT OPC$K_MAXMESSAGE = 2048
      DECLARE LONG CONSTANT OPC$K_COMHDRSIZ = 38
      DECLARE LONG CONSTANT OPC$_OPCOMERROR = 99999  !  New error message
      DECLARE LONG CONSTANT OPC$_X_OPRENABLE = 10
      DECLARE LONG CONSTANT OPC$_X_LOGFILE = 11
      DECLARE LONG CONSTANT OPC$_X_REQUEST = 12
      DECLARE LONG CONSTANT OPC$_X_REPLY = 13
      DECLARE LONG CONSTANT OPC$_X_CANCEL = 14
      DECLARE LONG CONSTANT OPC$_X_STATUS = 15
      DECLARE LONG CONSTANT OPC$_X_SHUTDOWN = 16
      DECLARE LONG CONSTANT OPC$_X_TIMESTAMP = 17
      DECLARE LONG CONSTANT OPC$_X_SECURITY = 18
      DECLARE LONG CONSTANT OPC$_X_CLUSMSG = 19
      DECLARE LONG CONSTANT OPC$_X_DEBUG = 20
      DECLARE LONG CONSTANT OPC$_X_CNXMAN = 21
      DECLARE LONG CONSTANT OPC$_X_REQUEST_END_MARK = 22
      DECLARE LONG CONSTANT OPC$K_CLM__ACKNOWLEDGEMENT = 1  !  Response to acknowledge request
      DECLARE LONG CONSTANT OPC$K_CLM__ACKNOWLEDGE_PLEASE = 2  !  Request for remote node to announce itself
      DECLARE LONG CONSTANT OPC$K_CLM__CANCEL = 3  !  Explicit cancel of request
      DECLARE LONG CONSTANT OPC$K_CLM__CHECK_OPERATOR = 4  !  Make sure this operator is in the database
      DECLARE LONG CONSTANT OPC$K_CLM__CHECK_REQUEST = 5  !  Make sure a request is in the database
      DECLARE LONG CONSTANT OPC$K_CLM__CLUMBX = 6  !  Cluster mailbox message passed from cnxman
      DECLARE LONG CONSTANT OPC$K_CLM__CLUSTER = 7  !  Cluster status change report
      DECLARE LONG CONSTANT OPC$K_CLM__DEVICE = 8  !  Device message (on-line, off-line etc)
      DECLARE LONG CONSTANT OPC$K_CLM__IMP_CANCEL = 9  !  Implicitly cancel a request
      DECLARE LONG CONSTANT OPC$K_CLM__IMP_DISABLE = 10  !  Implicitly disable an operator
      DECLARE LONG CONSTANT OPC$K_CLM__OPRENABLE = 11  !  Tell everyone else to enable or disable an operator
      DECLARE LONG CONSTANT OPC$K_CLM__REPLY = 12  !  REPLY /PEND etc command
      DECLARE LONG CONSTANT OPC$K_CLM__REPLY_COMPLETE = 13  !  Operator request completed by operator
      DECLARE LONG CONSTANT OPC$K_CLM__REQUEST = 14  !  Operator request
      DECLARE LONG CONSTANT OPC$K_CLM__RPYBRD = 15  !  Message from OPCOM to remotes, info for cluster REPLY /TERM, etc
      DECLARE LONG CONSTANT OPC$K_CLM__RPYBRD_LOCAL = 16  !  Broadcast message from REPLY to OPCOM on local node
      DECLARE LONG CONSTANT OPC$K_CLM__RPYNOT = 17  !  Reply notifications
      DECLARE LONG CONSTANT OPC$K_CLM__SECURITY = 18  !  Security alarm from remote
      DECLARE LONG CONSTANT OPC$K_CLM__SHUTDOWN = 19  !  Shut down operations
      DECLARE LONG CONSTANT OPC$K_CLM__LOGFILE = 20  !  Enable/disable logfile operator
      DECLARE LONG CONSTANT OPC$K_CLM__REQUEST_END_MARK = 21
      DECLARE LONG CONSTANT OPC$K_HDR_SIZE = 26  !  Size of common header
      DECLARE LONG CONSTANT OPC$S_HEADER_MESSAGE = 26
      record HEADER_MESSAGE
         BYTE OPC$B_RQSTCODE                !  Request code
         BYTE OPC$B_SCOPE                   !  Request SCOPE
         LONG OPC$L_OPTIONS                 !  Request independent option bits.
         group OPC$R_RQOPT
            variant
               case
                  LONG OPC$L_RQ_OPTIONS     !  Request dependent options
               case
                  group OPC$R_RQ_OPT_S      !  Also make it available as
                     BYTE OPC$B_RQOPT_CODE  !   a code byte and some fill
                     BYTE OPC$B_RQOPT_FILLb
                     WORD OPC$W_RQOPT_FILLw
                  end group OPC$R_RQ_OPT_S
            end variant
         end group OPC$R_RQOPT
         LONG OPC$L_ATTNMASK1               !  Attention mask part 1
         LONG OPC$L_ATTNMASK2               !  Attention mask part 2
         LONG OPC$L_RQSTID                  !  User specified request id #
         LONG OPC$L_UIC                     !  UIC of requestor
      end record HEADER_MESSAGE
    
      DECLARE LONG CONSTANT OPC$M_NOLOG = x'00000001'
      DECLARE LONG CONSTANT OPC$M_NOBRD = x'00000002'
      DECLARE LONG CONSTANT OPC$M_NOCLUSTER = x'00000004'
      DECLARE LONG CONSTANT OPC$S_FILL_0_ = 4
      record FILL_0_
         variant
            case
               LONG OPC$L_HEADER_OPTIONS
            case
               group OPC$R_FILL_1_
                   !  Do not log the action
                   !  Do not broadcast
                   !  Do not send to cluster
                  BYTE NOLOG_bits   ! COMMENT ADDED BY SDL - NOLOG_bits contains bits NOLOG through FILL_2_
               end group OPC$R_FILL_1_
         end variant
      end record FILL_0_
    
      DECLARE LONG CONSTANT OPC$K_OPRENABLE_MIN_SIZE = 30  !  Min message size header + 4
      DECLARE LONG CONSTANT OPC$S_OPRENABLE_MESSAGE = 26
      record OPRENABLE_MESSAGE
         BYTE OPC$B_OPRENABLE_FILL ( 1 to 26 )
         STRING OPC$T_OPRENABLE_OPR = 0     !  Start of oper dev name
      end record OPRENABLE_MESSAGE
    
      DECLARE LONG CONSTANT OPC$M_DISABLE = x'00000001'
      DECLARE LONG CONSTANT OPC$M_PERMOPER = x'00000002'
      DECLARE LONG CONSTANT OPC$M_NOREMIND = x'00000004'
      DECLARE LONG CONSTANT OPC$S_FILL_3_ = 4
      record FILL_3_
         variant
            case
               LONG OPC$L_OPRENABLE_OPTIONS
            case
               group OPC$R_FILL_4_
                  BYTE DISABLE_bits   ! COMMENT ADDED BY SDL - DISABLE_bits contains bits DISABLE through FILL_5_
               end group OPC$R_FILL_4_
         end variant
      end record FILL_3_
    
      DECLARE LONG CONSTANT OPC$K_LOGFILE_MIN_SIZE = 30  !  Min message size header + 4
      DECLARE LONG CONSTANT OPC$K_INITLOG = 0  !  If one is open, close logfile.  Open new logfile.
      DECLARE LONG CONSTANT OPC$K_CLOSELOG = 1  !  Close logfile.
      DECLARE LONG CONSTANT OPC$K_ENABLELOG = 2  !  If no logfile is open, open a logfile.
    !    Add classes in ATTNMASK to logfile operator mask.
      DECLARE LONG CONSTANT OPC$K_DISABLELOG = 3  !  Remove classes in ATTNMASK from logfile operator mask.
    !    If mask goes to 0, close logfile.
      DECLARE LONG CONSTANT OPC$K_MAX_LOGOPT = 4  !  One more than maximum allowed
      DECLARE LONG CONSTANT OPC$S_LOGFILE_MESSAGE = 26
      record LOGFILE_MESSAGE
         BYTE OPC$B_LOGFILE_FILL ( 1 to 26 )   !  Skip to request dependent options
         STRING OPC$T_LOGFILE_OPR = 0       !  Start of oper dev name
      end record LOGFILE_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_REQUEST_MIN_SIZE = 28  !  Min message size
      DECLARE LONG CONSTANT OPC$S_REQUEST_MESSAGE = 28
      record REQUEST_MESSAGE
         BYTE OPC$B_REQUEST_FILL ( 1 to 26 )
         WORD OPC$W_REQUEST_LENGTH          !  Length of text
         STRING OPC$T_REQUEST_TEXT = 0      !  Start of text
      end record REQUEST_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_SECURITY_MIN_SIZE = 28  !  Min message size
      DECLARE LONG CONSTANT OPC$S_SECURITY_MESSAGE = 28
      record SECURITY_MESSAGE
         BYTE OPC$B_SECURITY_FILL ( 1 to 26 )
         WORD OPC$W_SECURITY_LENGTH         !  Length of text
         STRING OPC$T_SECURITY_TEXT = 0     !  Start of text
      end record SECURITY_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_REPLY_MIN_SIZE = 32
      DECLARE LONG CONSTANT OPC$S_REPLY_MESSAGE = 26
      record REPLY_MESSAGE
         BYTE OPC$B_REPLY_FILL ( 1 to 26 )
         STRING OPC$T_REPLY_OPR = 0
      end record REPLY_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_STATUS_MIN_SIZE = 30  !  Min message size header + 4
      DECLARE LONG CONSTANT OPC$S_STATUS_MESSAGE = 26
      record STATUS_MESSAGE
         BYTE OPC$B_STATUS_FILL ( 1 to 26 )
         STRING OPC$T_STATUS_OPR = 0        !  Start of text
      end record STATUS_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_TIMESTAMP_MIN_SIZE = 26  !  Min message size
      DECLARE LONG CONSTANT OPC$S_TIMESTAMP_MESSAGE = 26
      record TIMESTAMP_MESSAGE
         BYTE OPC$B_TIMESTAMP_FILL ( 1 to 26 )
      end record TIMESTAMP_MESSAGE
    
      DECLARE LONG CONSTANT OPC$K_SHUTDOWN_MIN_SIZE = 26  !  Min message size
      DECLARE LONG CONSTANT OPC$S_SHUTDOWN_MESSAGE = 26
      record SHUTDOWN_MESSAGE
         BYTE OPC$B_SHUTDOWN_FILL ( 1 to 26 )
      end record SHUTDOWN_MESSAGE
    
      DECLARE LONG CONSTANT OPC$M_CLUSTER = x'00000001'
      DECLARE LONG CONSTANT OPC$S_FILL_6_ = 4
      record FILL_6_
         variant
            case
               LONG OPC$L_SHUTDOWN_OPTIONS
            case
               group OPC$R_FILL_7_
                  BYTE CLUSTER_bits   ! COMMENT ADDED BY SDL - CLUSTER_bits contains bits CLUSTER through FILL_8_
               end group OPC$R_FILL_7_
         end variant
      end record FILL_6_
    
      DECLARE LONG CONSTANT OPC$K_CANCEL_MIN_SIZE = 26  !  Min message size
      DECLARE LONG CONSTANT OPC$S_CANCEL_MESSAGE = 26
      record CANCEL_MESSAGE
         BYTE OPC$B_CANCEL_FILL ( 1 to 26 )
      end record CANCEL_MESSAGE
    
      DECLARE LONG CONSTANT OPC$M_RQSTDONE = x'00000001'
      DECLARE LONG CONSTANT OPC$S_FILL_9_ = 4
      record FILL_9_
         variant
            case
               LONG OPC$L_CANCEL_OPTIONS
            case
               group OPC$R_FILL_10_
                  BYTE RQSTDONE_bits   ! COMMENT ADDED BY SDL - RQSTDONE_bits contains bits RQSTDONE through FILL_11_
               end group OPC$R_FILL_10_
         end variant
      end record FILL_9_
    
      DECLARE LONG CONSTANT OPCF_ARG$S_OPCF_ARG = 4
      record OPCF_ARG
         variant
            case
               LONG OPCF_ARG$l_arg_data     !  argument data
            case
               group OPCF_ARG$r_arg_desc
                  WORD OPCF_ARG$w_arg_offset  !  The offset to the argument data
                  WORD OPCF_ARG$w_arg_cntrl  !  A control code for argument handling
               end group OPCF_ARG$r_arg_desc
         end variant
      end record OPCF_ARG
    
    !  This structure defines a message sent to OPCOM using the MSG$_OPCFAO message type.
      DECLARE LONG CONSTANT OPCF$S_OPCFAO = 256
      record OPCFAO
         WORD OPCF$w_msgtype                !  Dispatch message type code
         WORD OPCF$w_spare_1                !  Unused word - alignment
         LONG OPCF$l_opc_msg                !  The message file code for msg text
         LONG OPCF$l_opc_class_msk          !  The operator class mask
         LONG OPCF$l_arg_count              !  The number of arguments
         group OPCF$r_variable_data
            variant
               case
                  OPCF_ARG OPCF$r_item_arg ( 1 to 60 )  !  Argument items
               case
                  STRING OPCF$t_item_cd = 240  !  Argument data - character
               case
                  LONG OPCF$l_item_ld ( 1 to 60 )  !  Argument data - long
            end variant
         end group OPCF$r_variable_data
      end record OPCFAO
    
    !  OPCFAO option codes.  Unless commented otherwise, these codes correspond to
    !  the equivalent FAO op code (e.g. ?AC --> AC, ?%T --> T).  These codes are
    !  used as input arguments to exe_std$sndopcfao as controls.
      DECLARE LONG CONSTANT OPCF$K_AC = 1
      DECLARE LONG CONSTANT OPCF$K_AD = 2
      DECLARE LONG CONSTANT OPCF$K_AF = 3
      DECLARE LONG CONSTANT OPCF$K_AS = 4
      DECLARE LONG CONSTANT OPCF$K_AS_DEVICE_NAME = 5  !  Pass UCB for conversion to device name string with descriptor
      DECLARE LONG CONSTANT OPCF$K_AZ = 6
      DECLARE LONG CONSTANT OPCF$K_D = 7
      DECLARE LONG CONSTANT OPCF$K_I = 8
      DECLARE LONG CONSTANT OPCF$K_OA = 9
      DECLARE LONG CONSTANT OPCF$K_OB = 10
      DECLARE LONG CONSTANT OPCF$K_OH = 11
      DECLARE LONG CONSTANT OPCF$K_OI = 12
      DECLARE LONG CONSTANT OPCF$K_OJ = 13
      DECLARE LONG CONSTANT OPCF$K_OL = 14
      DECLARE LONG CONSTANT OPCF$K_OQ = 15
      DECLARE LONG CONSTANT OPCF$K_OW = 16
      DECLARE LONG CONSTANT OPCF$K_SA = 17
      DECLARE LONG CONSTANT OPCF$K_SB = 18
      DECLARE LONG CONSTANT OPCF$K_SH = 19
      DECLARE LONG CONSTANT OPCF$K_SI = 20
      DECLARE LONG CONSTANT OPCF$K_SJ = 21
      DECLARE LONG CONSTANT OPCF$K_SL = 22
      DECLARE LONG CONSTANT OPCF$K_SQ = 23
      DECLARE LONG CONSTANT OPCF$K_SW = 24
      DECLARE LONG CONSTANT OPCF$K_T = 25
      DECLARE LONG CONSTANT OPCF$K_U = 26
      DECLARE LONG CONSTANT OPCF$K_UA = 27
      DECLARE LONG CONSTANT OPCF$K_UB = 28
      DECLARE LONG CONSTANT OPCF$K_UH = 29
      DECLARE LONG CONSTANT OPCF$K_UI = 30
      DECLARE LONG CONSTANT OPCF$K_UJ = 31
      DECLARE LONG CONSTANT OPCF$K_UL = 32
      DECLARE LONG CONSTANT OPCF$K_UQ = 33
      DECLARE LONG CONSTANT OPCF$K_UW = 34
      DECLARE LONG CONSTANT OPCF$K_XA = 35
      DECLARE LONG CONSTANT OPCF$K_XB = 36
      DECLARE LONG CONSTANT OPCF$K_XH = 37
      DECLARE LONG CONSTANT OPCF$K_XI = 38
      DECLARE LONG CONSTANT OPCF$K_XJ = 39
      DECLARE LONG CONSTANT OPCF$K_XL = 40
      DECLARE LONG CONSTANT OPCF$K_XQ = 41
      DECLARE LONG CONSTANT OPCF$K_XW = 42
      DECLARE LONG CONSTANT OPCF$K_ZA = 43
      DECLARE LONG CONSTANT OPCF$K_ZB = 44
      DECLARE LONG CONSTANT OPCF$K_ZH = 45
      DECLARE LONG CONSTANT OPCF$K_ZI = 46
      DECLARE LONG CONSTANT OPCF$K_ZJ = 47
      DECLARE LONG CONSTANT OPCF$K_ZL = 48
      DECLARE LONG CONSTANT OPCF$K_ZQ = 49
      DECLARE LONG CONSTANT OPCF$K_ZW = 50
      DECLARE LONG CONSTANT OPCF$K_MIN_OPCFAO_CNTRL = 1
      DECLARE LONG CONSTANT OPCF$K_MAX_OPCFAO_CNTRL = 50
      DECLARE LONG CONSTANT OPCF$K_BY_REF = 1  !  Pass argument by reference
      DECLARE LONG CONSTANT OPCF$K_BY_VAL = 2  !  Pass argument by value
      DECLARE LONG CONSTANT OPCF$K_BY_DESC = 3  !  Pass argument by descriptor