RUI_BID

The RUI_BID verb notifies the RUI application that a message is waiting to be read using RUI_READ.

The following structure describes the LUA_COMMON member of the VCB used by RUI_BID.

struct LUA_COMMON {
    unsigned short lua_verb;
    unsigned short lua_verb_length;
    unsigned short lua_prim_rc;
    unsigned long  lua_sec_rc;
    unsigned short lua_opcode;
    unsigned long  lua_correlator;
    unsigned char  lua_luname[8];
    unsigned short lua_extension_list_offset;
    unsigned short lua_cobol_offset;
    unsigned long  lua_sid;
    unsigned short lua_max_length;
    unsigned short lua_data_length;
    char FAR *     lua_data_ptr;
    unsigned long  lua_post_handle;
    struct LUA_TH  lua_th;
    struct LUA_RH  lua_rh;
    struct LUA_FLAG1 lua_flag1;
    unsigned char  lua_message_type;
    struct LUA_FLAG2 lua_flag2; 
    unsigned char  lua_resv56[7];
    unsigned char  lua_encr_decr_option;
};

The following union describes the LUA_SPECIFIC member of the VCB used by RUI_BID. Other union members are omitted for clarity.

union LUA_SPECIFIC {
    unsigned char lua_peek_data[12];
};

Members

lua_verb
Supplied parameter. Contains the verb code, LUA_VERB_RUI for RUI verbs.
lua_verb_length
Supplied parameter. Specifies the length in bytes of the LUA VCB. It must contain the length of the verb record being issued.
lua_prim_rc
Primary return code set by LUA at the completion of the verb. The valid return codes vary depending on the LUA verb issued.
lua_sec_rc
Secondary return code set by LUA at the completion of the verb. The valid return codes vary depending on the LUA verb issued.
lua_opcode
Supplied parameter. Contains the LUA command code (verb operation code) for the verb to be issued, LUA_OPCODE_RUI_BID.
lua_correlator
Supplied parameter. Contains a user-supplied value that links the verb with other user-supplied information. LUA does not use or change this information. This parameter is optional.
lua_luname
Supplied parameter. Specifies the ASCII name of the local LU used by the Windows LUA session.

RUI_BID only requires this parameter if lua_sid is zero.

This parameter is eight bytes long, padded on the right with spaces (0x20) if the name is shorter than eight characters.

lua_extension_list_offset
Not used by RUI in Microsoft® SNA Server and should be set to zero.
lua_cobol_offset
Not used by LUA in SNA Server and should be zero.
lua_sid
Supplied parameter. Specifies the session identifier and is returned by SLI_OPEN and RUI_INIT. Other verbs use this parameter to identify the session used for the command. If other verbs use the lua_luname parameter to identify sessions, set the lua_sid parameter to zero.
lua_max_length
Not used by RUI_BID and should be set to zero.
lua_data_length
Returned parameter. Specifies the length of data returned in lua_peek_data for RUI_BID.
lua_data_ptr
Pointer to the application-supplied buffer that contains the data to be sent for SLI_SEND and RUI_WRITE or that will receive data for SLI_RECEIVE and RUI_READ. For other RUI and SLI verbs, this parameter is not used and should be set to zero.
lua_post_handle
Supplied parameter. Used under Microsoft® Windows NT® and Microsoft® Windows® 95 if asynchronous notification is to be accomplished by events. This variable contains the handle of the event to be signaled or a window handle.

For all other environments, this parameter is reserved and should be set to zero.

lua_th
Returned parameter. Contains the SNA transmission header (TH) of the message received. Various subparameters are set for write functions and returned for read and bid functions. Its subparameters are as follows:
lua_th.flags_fid
Format identification type 2, four bits.
lua_th.flags_mpf
Segmenting mapping field, two bits. Defines the type of data segment. The following values are valid:

0x00Middle segment
0x04Last segment
0x08First segment
0x0COnly segment

lua_th.flags_odai
Originating address field–destination address field (OAF–DAF) assignor indicator, one bit.
lua_th.flags_efi
Expedited flow indicator, one bit.
lua_th.daf
Destination address field (DAF), an unsigned char.
lua_th.oaf
Originating address field (OAF), an unsigned char.
lua_th.snf
Sequence number field, an unsigned char[2].
lua_rh
Returned parameter. Contains the SNA request/response header (RH) of the message sent or received. It is set for the write function and returned by the read and bid functions. Its subparameters are as follows:
lua_rh.rri
Request-response indicator, one bit.
lua_rh.ruc
RU category, two bits. The following values are valid:

LUA_RH_FMD (0x00)FM data segment
LUA_RH_NC (0x20)Network control
LUA_RH_DFC (0x40)Data flow control
LUA_RH_SC (0x60)Session control

lua_rh.fi
Format indicator, one bit.
lua_rh.sdi
Sense data included indicator, one bit.
lua_rh.bci
Begin chain indicator, one bit.
lua_rh.eci
End chain indicator, one bit.
lua_rh.dr1i
Definite response 1 indicator, one bit.
lua_rh.dr2i
Definite response 2 indicator, one bit.
lua_rh.ri
Exception response indicator (for a request), or response type indicator (for a response), one bit.
lua_rh.qri
Queued response indicator, one bit.
lua_rh.pi
Pacing indicator, one bit.
lua_rh.bbi
Begin bracket indicator, one bit.
lua_rh.ebi
End bracket indicator, one bit.
lua_rh.cdi
Change direction indicator, one bit.
lua_rh.csi
Code selection indicator, one bit.
lua_rh.edi
Enciphered data indicator, one bit.
lua_rh.pdi
Padded data indicator, one bit.
lua_flag1
Supplied parameter. Contains a data structure containing flags for messages supplied by the application. Its subparameters are as follows:
lua_flag1.bid_enable
Bid enable indicator, one bit.
lua_flag1.close_abend
Close immediate indicator, one bit.
lua_flag1.nowait
No wait for data flag, one bit.
lua_flag1.sscp_exp
SSCP expedited flow, one bit.
lua_flag1.sscp_norm
SSCP normal flow, one bit.
lua_flag1.lu_exp
LU expedited flow, one bit.
lua_flag1.lu_norm
LU normal flow, one bit.
lua_message_type
Returned parameter. Specifies the type of SNA message indicated to RUI_BID. Possible values are:

LUA_MESSAGE_TYPE_LU_DATA

LUA_MESSAGE_TYPE_SSCP_DATA

LUA_MESSAGE_TYPE_BID

LUA_MESSAGE_TYPE_BIND

LUA_MESSAGE_TYPE_BIS

LUA_MESSAGE_TYPE_CANCEL

LUA_MESSAGE_TYPE_CHASE

LUA_MESSAGE_TYPE_CLEAR

LUA_MESSAGE_TYPE_CRV

LUA_MESSAGE_TYPE_LUSTAT_LU

LUA_MESSAGE_TYPE_LUSTAT_SSCP

LUA_MESSAGE_TYPE_QC

LUA_MESSAGE_TYPE_QEC

LUA_MESSAGE_TYPE_RELQ

LUA_MESSAGE_TYPE_RQR

LUA_MESSAGE_TYPE_RTR

LUA_MESSAGE_TYPE_SBI

LUA_MESSAGE_TYPE_SHUTD

LUA_MESSAGE_TYPE_SIGNAL

LUA_MESSAGE_TYPE_SDT

LUA_MESSAGE_TYPE_STSN

LUA_MESSAGE_TYPE_UNBIND

The SLI receives and responds to the bind, crv, and stsn requests through the LUA interface extension routines.

lu_data, lustat_lu, lustat_sscp, and sscp_data are not SNA commands.

lua_flag2
Returned parameter. Contains flags for messages returned by LUA. Its subparameters are as follows:
lua_flag2.bid_enable
Indicates that RUI_BID was successfully re-enabled if set to 1.
lua_flag2.async
Indicates that the LUA interface verb completed asynchronously if set to 1.
lua_flag2.sscp_exp
Indicates SSCP expedited flow if set to 1.
lua_flag2.sscp_norm
Indicates SSCP normal flow if set to 1.
lua_flag2.lu_exp
Indicates LU expedited flow if set to 1.
lua_flag2.lu_norm
Indicates LU normal flow if set to 1.
lua_resv56
Reserved and should be set to zero.
lua_encr_decr_option
Reserved and should be set to zero.
lua_peek_data
The union member of LUA_SPECIFIC used by the RUI_BID and SLI_BID verbs. Returned parameter. Contains up to 12 bytes of the data waiting to be read.

Return Codes

lua_ok
Primary return code; the verb executed successfully.
lua_canceled
Primary return code; the verb did not complete successfully because it was canceled by another verb.
lua_terminated
Secondary return code; RUI_TERM was issued while this verb was pending.
LUA_PARAMETER_CHECK
Primary return code; the verb did not execute because of a parameter error.
LUA_BAD_SESSION_ID
Secondary return code; an invalid value for lua_sid was specified in the VCB.
LUA_BID_ALREADY_ENABLED
Secondary return code; RUI_BID was rejected because a previous RUI_BID was already outstanding. Only one RUI_BID can be outstanding at any one time.
LUA_INVALID_POST_HANDLE
Secondary return code; for a Windows NT or Windows 95 system using events as the asynchronous posting method, the Windows LUA VCB does not contain a valid event handle.

For a Windows version 3.x system, the Windows LUA VCB does not contain the valid procedure address returned by the MakeProcInstance command.

For OS/2, the Windows LUA VCB does not contain a valid semaphore or queue handle, which is needed when the verb completes asynchronously.

LUA_RESERVED_FIELD_NOT_ZERO
Secondary return code; a reserved field in the verb record, or a parameter not used by this verb, was set to a nonzero value.
LUA_VERB_LENGTH_INVALID
Secondary return code; an LUA verb was issued with the value of lua_verb_length unexpected by LUA.
LUA_STATE_CHECK
Primary return code; the verb did not execute because it was issued in an invalid state.
LUA_NO_RUI_SESSION
Secondary return code; RUI_INIT has not yet completed successfully for the LU name specified on this verb.
LUA_UNSUCCESSFUL
Primary return code; the verb record supplied was valid, but the verb did not complete successfully.
LUA_INVALID_PROCESS
Secondary return code; the process that issued this verb was not the same process that issued RUI_INIT for this session. Only the process that started a session can issue verbs on that session.
LUA_NEGATIVE_RSP
Primary return code; LUA detected an error in the data received from the host. Instead of passing the received message to the application on RUI_READ, LUA discards the message (and the rest of the chain if it is in a chain), and sends a negative response to the host.

LUA informs the application on a subsequent RUI_READ or RUI_BID that a negative response was sent.

The secondary return code contains the sense code sent to the host on the negative response. See SNA Considerations for information on interpreting the sense code values that can be returned.

A zero secondary return code indicates that, following a previous RUI_WRITE of a negative response to a message in the middle of a chain, LUA has now received and discarded all messages from this chain.

LUA_COMM_SUBSYSTEM_ABENDED
Primary return code; indicates one of the following conditions:
LUA_SESSION_FAILURE
Primary return code; a required SNA Server component has terminated.
LUA_LU_COMPONENT_DISCONNECTED
Secondary return code; indicates that the LUA session has failed because of a problem with the link service or with the host LU.
LUA_RUI_LOGIC_ERROR
Secondary return code; an internal error was detected within LUA. This error should not occur during normal operation.
LUA_INVALID_VERB
Primary return code; either the verb code or the operation code, or both, is invalid. The verb did not execute.
LUA_STACK_TOO_SMALL
Primary return code; the stack size of the application is too small to execute the verb. Increase the stack size of your application.
LUA_COMM_SUBSYSTEM_NOT_LOADED
Primary return code; a required component could not be loaded or has terminated while processing the verb. Thus, communication could not take place. Contact the system administrator for corrective action.
LUA_UNEXPECTED_DOS_ERROR
Primary return code; after issuing an operating system call, an unexpected operating system return code was received and is specified in the secondary return code.

Remarks

RUI_BID is used by applications that require notification that a message is waiting to be read. This allows the application to determine how it will handle the message before issuing RUI_READ.

When a message is available, RUI_BID returns with details of the message flow on which it was received, the message type, the TH and RH of the message, and up to 12 bytes of message data.

The main difference between RUI_BID and RUI_READ is that RUI_BID allows the application to check the data without removing it from the incoming message queue, so it can be left and accessed later. RUI_READ removes the message from the queue, so when the application reads the data it must also process it.

Note the following when using RUI_BID:

Each message that arrives is bid only once. After RUI_BID indicates that data is waiting on a particular session flow, the application issues RUI_READ to receive the data. Any subsequent RUI_BID does not report data arriving on that session flow until the message that was bid has been accepted by issuing RUI_READ.

In general, the lua_data_length parameter returned on this verb indicates only the length of data in lua_peek_data, not the total length of data on the waiting message (except when a value of less than 12 is returned). The application should ensure that the data length on RUI_READ that accepts the data is sufficient to contain the message.

See Also

RUI_INIT, RUI_READ, RUI_TERM, RUI_WRITE, SLI_OPEN