INQUIRE →     RPL:     ACB field → ACB
                       Note: ECB and EXIT are mutually exclusive.
                       If ECB is used, only one is allowed.
                       ECB field → external ECB
                       ECB field = internal ECB
                       EXIT field → RPL exit routine
                       BRANCH field = YES|NO
                       OPTCD field = (LOGONMSG|DEVCHAR|COUNTS|
                                       TERMS|APPSTAT|NQN|CIDXLATE|
                                       TOPLOGON|SESSPARM|SESSKEY|
                                       USERVAR|PERSESS|SESSNAME|
                                       STATUS|SYN|ASY)
 
                  If OPTCD = LOGONMSG
                       Note: ARG and NIB are mutually exclusive.
                       ARG field = CID of pending active session
                       NIB field → NIB:
                            Note: NAME and CID
                            are mutually exclusive.
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            CID field = CID of pending active session
                            LISTEND field = YES
                       AREA field → input area for user data from CINIT
                       AREALEN field = length of input area
 
           If OPTCD = DEVCHAR
                       Note: ARG and NIB are mutually exclusive.
                       ARG field = CID of session or pending
                                       active session
                       NIB field → NIB:
                            Note: NAME and CID
                            are mutually exclusive.
                            NAME field = symbolic name of
                                       logical unit
                            NETID field = symbolic network identifier of
                                       logical unit
                            CID field = CID of session or pending
                                       active session
                            LISTEND field = YES
                       AREA FIELD → input are for LU characteristics
                       AREALEN field = 8
 
           If OPTCD = TERMS
                       NIB field → NIB:
                            NAME field = symbolic name of resource
                                       in VTAM configuration tables
                            NETID field = symbolic network identifier of resource
                                       in VTAM configuration tables
                            LISTEND field = YES
                       AREA field → work area where NIBs are built
                       AREALEN field = length of work area
 
           If OPTCD = COUNTS
                       AREA field → input area for data
                       AREALEN field = 4
 
           If OPTCD = APPSTAT
                       NIB field → NIB:
                            NAME field = symbolic name of
                                       application program
                            NETID field = symbolic network identifier of
                                       application program
                            LISTEND field = YES
                       AREA field → network identifier and the real name
                            for specified application program
                       AREALEN field = length of output area
 
           If OPTCD = NQN
                       NIB field → NIB:
                            NAME field = symbolic name
                            NETID field = symbolic network identifier
                            LISTEND field = YES
                       AREA field → output name (based on type of
                            translation request)
                       AREALEN field = length of output area
 
           If OPTCD = CIDXLATE
                       Note: ARG and NIB are mutually exclusive.
                       ARG field = CID to be translated
                       NIB field → NIB:
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            LISTEND field = YES
                       AREA field → input area of symbolic name
                       AREALEN field = 8 for CID-to-name-translate
                                     = 4 for name-to-CID translate
 
           If OPTCD = TOPLOGON
                       AREA field → input area for symbolic name
                       AREALEN field = 8
 
           If OPTCD = SESSNAME
                       NIB field → NIB:
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            GNAME field = generic name of application
                            LISTEND field = YES
                       AREA field → area for application network name
                       AREALEN field = 16
 
           If OPTCD = SESSPARM
                       Note: ARG and NIB are mutually exclusive.
                       ARG field = CID of pending active session
                       NIB field → NIB:
                            Note: NAME and CID
                            are mutually exclusive.
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            CID field = CID of pending active session
                            LOGMODE field = |0 C‘|’logon mode name
                            LISTEND field = YES
                       AREA field → input area for session parameter
                       AREALEN field = length of input area
 
           If OPTCD = STATUS
                       NIB field → NIB:
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            LISTEND field = YES
                       AREA field → network identifier and the real name
                                 for specified LU
                       AREALEN field = length of output area
 
           If OPTCD = SESSKEY 
                       Note: ARG and NIB are mutually exclusive.
                       ARG field = CID of session
                       NIB field → NIB:
                            Note: NAME and CID
                            are mutually exclusive.
                            NAME field = symbolic name of LU
                            NETID field = symbolic network identifier of LU
                            CID field = CID of session
                            LISTEND field = YES
                       AREA field → input area for session
                                 cryptography key and initial
                                 chaining value
                       AREALEN field = 16
           If OPTCD = PERSESS 
                       AREA field → address of recovery data
                       AREALEN field = length of recovery data
 
 
     Registers 0 and 15 = return codes
 
     RPL:
          RTNCD field = recovery action return code
          FDB2 field = specific error return code
          REQ field = request code (26)
          SSENSEI field = CPM|STATE|FI|RR|PATH|0
          SSENSMI field = system-sense modifier value
                        (or 0)
          USENSEI field = user-sense value (or 0)
          RECLEN field = length of data received (if
                        (RTNCD,FDB2) = (X'00',X'05'),
                        RECLEN = total required length)
                        RECLEN = total required length
                        to identify one session
                        if OPTCD = PERSESS 
          FDBK field = status information if
                        OPTCD = APPSTAT or OPTCD = STATUS
          ARG field = CID of oldest pending active
                        session if OPTCD = TOPLOGON