QUERY_LU_0_TO_3
QUERY_LU_0_TO_3 returns information about local LUs of type 0, 1, 2, or 3. This information is structured as determined data (data gathered dynamically during execution) and defined data (the data supplied by the application on DEFINE_LU_0_TO_3).
The information is returned as a list in one of two formats, either summary or detailed information. To obtain information about a specific local LU, or to obtain the list information in several chunks, the lu_name field should be set. Otherwise (if the list_options field is set to AP_FIRST_IN_LIST), this field will be ignored.
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VCB Structure
typedef struct query_lu_0_to_3
{
unsigned short opcode; /* verb operation code */
unsigned char attributes; /* Verb attributes */
unsigned char reserv2; /* reserved */
unsigned char format; /* format */
unsigned short primary_rc; /* primary return code */
unsigned long secondary_rc; /* secondary return code */
unsigned char *buf_ptr; /* pointer to buffer */
unsigned long buf_size; /* buffer size */
unsigned long total_buf_size; /* total buffer size required */
unsigned short num_entries; /* number of entries */
unsigned short total_num_entries; /* total number of entries */
unsigned char list_options; /* listing options */
unsigned char reserv3; /* reserved */
unsigned char pu_name[8]; /* PU name filter */
unsigned char lu_name[8]; /* LU name */
unsigned char host_attachment; /* Host attachment filter */
} QUERY_LU_0_TO_3;typedef struct lu_0_to_3_summary
{
unsigned short overlay_size; /* size of this entry */
unsigned char pu_name[8]; /* PU name */
unsigned char lu_name[8]; /* LU name */
unsigned char description[RD_LEN];
/* resource description */
unsigned char nau_address; /* NAU address */
unsigned char lu_sscp_sess_active;
/* Is LU-SSCP session active */
unsigned char appl_conn_active; /* Is connection to appl active? */
unsigned char plu_sess_active; /* Is PLU-SLU session active */
unsigned char host_attachment; /* LU's host attachment */
} LU_0_TO_3_SUMMARY;typedef struct lu_0_to_3_detail
{
unsigned short overlay_size; /* size of this entry */
unsigned char lu_name[8]; /* LU name */
unsigned char reserv1[2]; /* reserved */
LU_0_TO_3_DET_DATA det_data; /* Determined data */
LU_0_TO_3_DEF_DATA def_data; /* Defined data */
} LU_0_TO_3_DETAIL;typedef struct lu_0_to_3_det_data
{
unsigned char lu_sscp_sess_active;
/* Is LU-SSCP session active */
unsigned char appl_conn_active; /* Application is using LU */
unsigned char plu_sess_active; /* Is PLU-SLU session active */
unsigned char host_attachment; /* Host attachment */
SESSION_STATS lu_sscp_stats; /* LU-SSCP session statistics */
SESSION_STATS plu_stats; /* PLU-SLU session statistics */
unsigned char plu_name[8]; /* PLU name */
unsigned char session_id[8]; /* Internal ID of PLU-SLU sess */
unsigned char app_spec_det_data[256];
/* Application Specified Data */
unsigned char app_type; /* Application type */
unsigned char sscp_id[6]; /* SSCP ID */
unsigned char bind_lu_type; /* LU type issuing BIND */
unsigned char reserva[12]; /* reserved */
} LU_0_TO_3_DET_DATA;typedef struct session_stats
{
unsigned short rcv_ru_size; /* session receive RU size */
unsigned short send_ru_size; /* session send RU size */
unsigned short max_send_btu_size; /* max send BTU size */
unsigned short max_rcv_btu_size; /* max rcv BTU size */
unsigned short max_send_pac_win; /* max send pacing win size */
unsigned short cur_send_pac_win; /* current send pacing win size */
unsigned short max_rcv_pac_win; /* max receive pacing win size */
unsigned short cur_rcv_pac_win; /* current receive pacing */
/* window size */
unsigned long send_data_frames; /* number of data frames sent */
unsigned long send_fmd_data_frames;
/* num of FMD data frames sent */
unsigned long send_data_bytes; /* number of data bytes sent */
unsigned long rcv_data_frames; /* num data frames received */
unsigned long rcv_fmd_data_frames;
/* num of FMD data frames recvd */
unsigned long rcv_data_bytes; /* number of data bytes received */
unsigned char sidh; /* session ID high byte */
unsigned char sidl; /* session ID low byte */
unsigned char odai; /* ODAI bit set */
unsigned char ls_name[8]; /* Link station name */
unsigned char pacing_type; /* type of pacing in use */
} SESSION_STATS;typedef struct lu_0_to_3_def_data
{
unsigned char description[RD_LEN];
/* resource description */
unsigned char nau_address; /* LU NAU address */
unsigned char pool_name[8]; /* LU Pool name */
unsigned char pu_name[8]; /* PU name */
unsigned char priority; /* LU priority */
unsigned char lu_model; /* LU model */
unsigned char sscp_id[6];
unsigned char timeout; /* Timeout */
unsigned char app_spec_def_data[16];
/* Application Specified Data */
unsigned char model_name[7]; /* LU model */
unsigned char reserv3[17]; /* reserved */
} LU_0_TO_3_DEF_DATA;Supplied Parameters
- opcode
- AP_QUERY_LU_0_TO_3
- attributes
- The attributes of the verb. This field is a bit field. The first
bit contains the visibility of the resource to be defined and corresponds
to one of the following:
AP_EXTERNALLY_VISIBLE
AP_INTERNALLY_VISIBLE - format
- Identifies the format of the VCB. Set this field to zero to specify the version of the VCB listed above.
- buf_ptr
- Pointer to a buffer into which list information can be written.
- buf_size
- Size of buffer supplied. The data returned will not exceed this size.
- num_entries
- Maximum number of entries to return. The number of entries will not exceed this value. A value of zero means no limit.
- list_options
- This indicates what should be returned in the list information.
- AP_SUMMARY
- Returns summary information only.

AP_SUMMARY value is also supported for SNA API clients. - AP_DETAIL
- Returns detailed information.
The lu_name specified (see the following parameter, lu_name) represents an index value that is used to specify the starting point of the actual information to be returned.
- AP_FIRST_IN_LIST
- The index value is ignored, and the returned list starts from
the first entry in the list
.

AP_FIRST_IN_LIST value is also supported for SNA API clients. - AP_LIST_FROM_NEXT
- The returned list starts from the next entry in the list after the one specified by the supplied index value.
- AP_LIST_INCLUSIVE
- The returned list starts from the entry specified by the index value.
- lu_name
- Name of the local LU that is being queried. This is an 8-byte
alphanumeric type-A EBCDIC string (starting with a letter), padded
to the right with EBCDIC spaces. This field is ignored if list_options is set to AP_FIRST_IN_LIST.

The list_options value is ignored for SNA API clients. - pu_name
- PU name. Only LUs that use this PU will be returned. If a list
of all LUs is required then this field should be set to all binary
zeros. The list_options value is ignored for SNA API clients. The
list_options value is ignored for SNA API clients.

The pu_name value is ignored for SNA API clients. - host_attachment
- Filter for host attachment.
- AP_NONE
- Return information about all LUs.

AP_NONE is the only value supported for SNA API clients. - AP_DLUR_ATTACHED
- Return information about all LUs that are supported by DLUR.
- AP_DIRECT_ATTACHED
- Return information about only those LUs that are directly attached to the host system.
Returned Parameters
- primary_rc
- AP_OK
- buf_size
- Length of the information returned in the buffer.
- total_buf_size
- Returned value indicating the size of buffer that would have been required to return all the list information requested. This can be higher than buf_size.
- num_entries
- Number of entries actually returned.
- total_num_entries
- Total number of entries that could have been returned. This can be higher than num_entries.
- lu_0_to_3_summary.overlay_size
- The number of bytes in this entry, and hence the offset to the next entry returned (if any).
- lu_0_to_3_summary.pu_name
- Name of local PU that this LU is using. This is an 8-byte alphanumeric
type-A EBCDIC string (starting with a letter), padded to the right
with EBCDIC spaces.

The lu_0_to_3_summary.pu_name value is not returned on SNA API clients. - lu_0_to_3_summary.lu_name
- Name of the local LU that is being queried. This is an 8-byte alphanumeric type-A EBCDIC string (starting with a letter), padded to the right with EBCDIC spaces.
- lu_0_to_3_summary.description
- Resource description (as specified on DEFINE_LU_0_TO_3). This
is a 16-byte string in a locally displayable character set. All 16
bytes are significant.

The lu_0_to_3_summary.description value is not returned on SNA API clients. - lu_0_to_3_summary.nau_address
- Network addressable unit address of the LU, which is in the
range 1–255.

The lu_0_to_3_summary.nau_address value is not returned on SNA API clients. - lu_0_to_3_summary.lu_sscp_sess_active
- Specifies whether the LU-SSCP session is active (AP_YES or AP_NO).

The lu_0_to_3_summary.lu_sscp_sess_active value is not returned on SNA API clients. - lu_0_to_3_summary.appl_conn_active
- Specifies whether an application is using the LU (AP_YES or
AP_NO).

The lu_0_to_3_summary.aapl_conn_active value is not returned on SNA API clients. - lu_0_to_3_summary.plu_sess_active
- Specifies whether the PLU-SLU session is active (AP_YES or AP_NO).

The lu_0_to_3_summary.plu_sess_active value is not returned on SNA API clients. - lu_0_to_3_summary.host_attachment
- LU host attachment type:
- AP_DLUR_ATTACHED
- LU is attached to host system using DLUR.
- AP_DIRECT_ATTACHED
- LU is directly attached to host system.
- lu_0_to_3_detail.overlay_size
- The number of bytes in this entry, and hence the offset to the next entry returned (if any).
- lu_0_to_3_detail.lu_name
- Name of the local LU that is being queried. This is an 8-byte alphanumeric type-A EBCDIC string (starting with a letter), padded to the right with EBCDIC spaces.
- lu_0_to_3_detail.det_data.lu_sscp_sess_active
- Specifies whether the LU-SSCP session is active (AP_YES or AP_NO).
- lu_0_to_3_detail.det_data.appl_conn_active
- Specifies whether this LU is currently being used by an application (AP_YES or AP_NO).
- lu_0_to_3_detail.det_data.plu_sess_active
- Specifies whether the PLU-SLU session is active (AP_YES or AP_NO).
- lu_0_to_3_detail.det_data.host_attachment
- LU host attachment type:
- AP_DLUR_ATTACHED
- LU is attached to host system using DLUR.
- AP_DIRECT_ATTACHED
- LU is directly attached to host system.
- lu_0_to_3_detail.det_data.lu_sscp_stats.rcv_ru_size
- This field is always reserved.
- lu_0_to_3_detail.det_data.lu_sscp_stats.send_ru_size
- This field is always reserved.
- lu_0_to_3_detail.det_data.lu_sscp_stats.max_send_btu_size
- Maximum BTU size that can be sent.
- lu_0_to_3_detail.det_data.lu_sscp_stats.max_rcv_btu_size
- Maximum BTU size that can be received.
- lu_0_to_3_detail.det_data.lu_sscp_stats.max_send_pac_win
- This field will always be set to zero.
- lu_0_to_3_detail.det_data.lu_sscp_stats.cur_send_pac_win
- This field will always be set to zero.
- lu_0_to_3_detail.det_data.lu_sscp_stats.max_rcv_pac_win
- This field will always be set to zero.
- lu_0_to_3_detail.det_data.lu_sscp_stats.cur_rcv_pac_win
- This field will always be set to zero.
- lu_0_to_3_detail.det_data.lu_sscp_stats.send_data_frames
- Number of normal flow data frames sent.
- lu_0_to_3_detail.det_data.lu_sscp_stats.send_fmd_data_frames
- Number of normal flow FMD data frames sent.
- lu_0_to_3_detail.det_data.lu_sscp_stats.send_data_bytes
- Number of normal flow data bytes sent.
- lu _0_to_3_detail.det_data.lu_sscp_stats.rcv_data_frames
- Number of normal flow data frames received.
- lu_0_to_3_detail.det_data.lu_sscp_stats.rcv_fmd_data_frames
- Number of normal flow FMD data frames received.
- lu_0_to_3_detail.det_data.lu_sscp_stats.rcv_data_bytes
- Number of normal flow data bytes received.
- lu_0_to_3_detail.det_data.lu_sscp_stats.sidh
- Session ID high byte.
- lu_0_to_3_detail.det_data.lu_sscp_stats.sidl
- Session ID low byte.
- lu_0_to_3_detail.det_data.lu_sscp_stats.odai
- Origin Destination Address Indicator. When bringing up a session, the sender of the ACTLU sets this field to zero if the local node contains the primary link station, and sets it to one if the ACTLU sender is the node containing the secondary link station.
- lu_0_to_3_detail.det_data.lu_sscp_stats.ls_name
- Link station name associated with statistics. This is an 8-byte string in a locally displayable character set. All 8 bytes are significant. This field can be used to correlate this session with the link over which the session flows.
- lu_0_to_3_detail.det_data.lu_sscp_stats.pacing_type
- Receive pacing type in use on the LU-SSCP session. This will be set to AP_NONE.
- lu_0_to_3_detail.det_data.plu_stats.rcv_ru_size
- Maximum receive RU size.
- lu_0_to_3_detail.det_data.plu_stats.send_ru_size
- Maximum send RU size.
- lu_0_to_3_detail.det_data.plu_stats.max_send_btu_size
- Maximum BTU size that can be sent.
- lu_0_to_3_detail.det_data.plu_stats.max_rcv_btu_size
- Maximum BTU size that can be received.
- lu_0_to_3_detail.det_data.plu_stats.max_send_pac_win
- Maximum size of the send pacing window on this session.
- lu_0_to_3_detail.det_data.plu_stats.cur_send_pac_win
- Current size of the send pacing window on this session.
- lu_0_to_3_detail.det_data.plu_stats.max_rcv_pac_win
- Maximum size of the receive pacing window on this session.
- lu_0_to_3_detail.det_data.plu_stats.cur_rcv_pac_win
- Current size of the receive pacing window on this session.
- lu_0_to_3_detail.det_data.plu_stats.send_data_frames
- Number of normal flow data frames sent.
- lu_0_to_3_detail.det_data.plu_stats.send_fmd_data_frames
- Number of normal flow FMD data frames sent.
- lu_0_to_3_detail.det_data.plu_stats.send_data_bytes
- Number of normal flow data bytes sent.
- lu_0_to_3_detail.det_data.plu_stats.rcv_data_frames
- Number of normal flow data frames received.
- lu_0_to_3_detail.det_data.plu_stats.rcv_fmd_data_frames
- Number of normal flow FMD data frames received.
- lu_0_to_3_detail.det_data.plu_stats.rcv_data_bytes
- Number of normal flow data bytes received.
- lu_0_to_3_detail.det_data.plu_stats.sidh
- Session ID high byte.
- lu_0_to_3_detail.det_data.plu_stats.sidl
- Session ID low byte.
- lu_0_to_3_detail.det_data.plu_stats.odai
- Origin Destination Address Indicator. When bringing up a session, the sender of the BIND sets this field to zero if the local node contains the primary link station, and sets it to one if the BIND sender is the node containing the secondary link station.
- lu_0_to_3_detail.det_data.plu_stats.ls_name
- Link station name associated with statistics. This is an 8-byte string in a locally displayable character set. All 8 bytes are significant.
- lu_0_to_3_detail.det_data.plu_stats.pacing_type
- Receive pacing type in use on the PLU-SSCP session. This can take the values AP_NONE or AP_PACING_FIXED.
- lu_0_to_3_detail.det_data.plu_name
- Primary LU name. This is an 8-byte alphanumeric type-A EBCDIC string (starting with a letter), padded to the right with EBCDIC spaces. (If the PLU-SLU session is inactive this field is reserved).
- lu_0_to_3_detail.det_data.session_id
- Eight byte internal identifier of the PLU-SLU session.
- lu_0_to_3_detail.det_data.app_spec_det_data
- Reserved.
- lu_0_to_3_detail.det_data.app_type
- Reserved.
- lu_0_to_3_detail.det_data.sscp_id
- This is a 6–byte field containing the SSCP ID received
in the ACTPU for the PU used by this LU.
If lu_sscp_sess_active is not AP_YES, then this field will be zeroed.
- lu_0_to_3_detail.det_data.bind_lu_type
- The LU type of the LU that issued the original BIND. If there
is an active LU-LU session, then this can be one of the following:
AP_LU_TYPE_0
AP_LU_TYPE_1
AP_LU_TYPE_2
AP_LU_TYPE_3
AP_LU_TYPE_6 (for downstream dependent LU 6.2)If there is no active LU—LU session, then this field takes the following value:
AP_LU_TYPE_UNKNOWN
- lu_0_to_3_detail.def_data.description
- Resource description (as specified on DEFINE_LU_0_TO_3). This is a 16-byte string in a locally displayable character set. All 16 bytes are significant.
- lu_0_to_3_detail.def_data.nau_address
- Network addressable unit address of the LU, which is in the range 1–255.
- lu_0_to_3_detail.def_data.pool_name
- Name of pool to which this LU belongs. This is an 8-byte alphanumeric type-A EBCDIC string (starting with a letter), padded to the right with EBCDIC spaces. If the LU does not belong to a pool, this field is set to all binary zeros.
- lu_0_to_3_detail.def_data.pu_name
- Name of the PU (as specified on the DEFINE_LS verb) that this LU will use. This is an 8-byte alphanumeric type-A EBCDIC string (starting with a letter), padded to the right with EBCDIC spaces.
- lu_0_to_3_detail.def_data.priority
- LU priority when sending to the host. This is set to one of
the following values:
AP_NETWORK
AP_HIGH
AP_MEDIUM
AP_LOW - lu_0_to_3_detail.def_data.lu_model
- Model type and number of the LU. This is set to one of the following
values:
AP_3270_DISPLAY_MODEL_2
AP_3270_DISPLAY_MODEL_3
AP_3270_DISPLAY_MODEL_4
AP_3270_DISPLAY_MODEL_5
AP_RJE_WKSTN
AP_PRINTER
AP_SCS_PRINTER
AP_UNKNOWN - lu_0_to_3_detail.def_data.sscp_id
- This field specifies the ID of the SSCP permitted to activate this LU. It is a 6–byte binary field. If the field is set to binary zeros, then the LU may be activated by any SSCP.
- lu_0_to_3_detail.def_data.timeout
- Timeout for LU specified in seconds. If a timeout is supplied
and the user of the LU specified allow_timeout on
the OPEN_LU_SSCP_SEC_RQ (or, in the case of PU concentration, on the
Downstream LU definition), then the LU will be deactivated after the
PLU-SLU session is left inactive for this period and one of the following
conditions holds:
- The session passes over a limited resource link
- Another application wishes to use the LU before the session is used again
If the timeout is set to zero, the LU will not be deactivated.
- lu_0_to_3_detail.def_data.app_spec_def_data
- Application-specified data from DEFINE_LU_0_TO_3; the Program does not interpret this field, it is simply stored and returned on the QUERY_LU_0_TO_3 verb.
- lu_0_to_3_detail.def_data.model_name
- The value returned is the value specified in the format 1 DEFINE_LU_0_TO_3 verb, or hex zeros if the DEFINE verb was format 0.
- primary_rc
- AP_PARAMETER_CHECK
- secondary_rc
- AP_INVALID_LU_NAME
AP_INVALID_LIST_OPTION
- primary_rc
- AP_NODE_NOT_STARTED
- primary_rc
- AP_UNEXPECTED_SYSTEM_ERROR