Programming Interface Information: This page documents intended Programming Interfaces that allow the customer to write programs to obtain the services of z/VM.

#### LABSECT

Prolog

Control Block Contents
LABSECT DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### LABSECT Prolog

     Name       : LABSECT
     Description: Tape Label Information
     DSECT      : LABSECT
     Function   : LABSECT contains user-supplied tape label
                  information used by CMS tape label processing.
                  LABSECT is called by the LABSECT macro.

#### LABSECT Control Block Content

#### LABSECT DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      LABSECT
    0000    0 Address      4 LABNEXT        FORWARD CHAIN POINTER
    0004    4 Address      4 LABFCBPT       POINTER TO FCBSECT OR ZERO
    0008    8 Character    8 LABFILE        NAME OF FILE (DDNAME) FOR BLOCK
    0010   16 Character   17 LABFID         FILE ID (RIGHTMOST 17 CHARACTERS)
    0021   33 Character    1 LABSEC         SECURITY
    0022   34 Character    6 LABVOLID       VOLUME SERIAL NUMBER (VOLID)
    0028   40 Character    4 LABVSEQ        VOLUME SEQUENCE NUMBER
    002C   44 Character    4 LABFSEQ        FILE SEQUENCE NUMBER
    0030   48 Character    4 LABGENN        GENERATION NUMBER
    0034   52 Character    2 LABGENV        GENERATION VERSION
    0036   54 Character    6 LABCRD         CREATION DATE
    003C   60 Character    6 LABEXD         EXPIRATION DATE
    0042   66 Bitstring    1 LABFLAG1       THIS BYTE HAS DEFAULT FLAGS:
              1... ....      LABDFID        X'80' DEFAULT FILE ID
              .1.. ....      LABDSEC        X'40' DEFAULT SECURITY
              ..1. ....      LABDVID        X'20' DEFAULT VOLUME SERIAL
                                            NUMBER
              ...1 ....      LABDVSEQ       X'10' DEFAULT VOLUME SEQUENCE
                                            NUMBER
              .... 1...      LABDFSEQ       X'08' DEFAULT FILE SEQUENCE
                                            NUMBER
              .... .1..      LABDGENN       X'04' DEFAULT GENERATION NUMBER
              .... ..1.      LABDGENV       X'02' DEFAULT GENERATION VERSION
              .... ...1      LABDCRD        X'01' DEFAULT CREATION DATE
    0043   67 Bitstring    1 LABFLAG2       MISCELLANEOUS FLAGS BYTE:
              1... ....      LABDEXD        X'80' DEFAULT EXPIRATION DATE
              .1.. ....      LABSCRAT       X'40' DO 'SCRATCH' VOLID
                                            PROCESSING
              ..1. ....      LABSCRSP       X'20' SCRATCH SPECIFIED; NOT
                                            DEFAULT
              ...1 ....      LABLBDSC       X'10' LABSCRAT set by LABELDEF
              .... .1..      LABFDEF        X'04' LABSECT GOTTEN BY FILEDEF
              .... ..1.      LABPERM        X'02' PERMANENT SPECIFIED
              .... ...1      LABNOCHG       X'01' NOCHANGE SPECIFIED
    0044   68 Address      4 LABCUVOL       POINTER TO CURRENT VOLID MOUNTED
    0048   72 Address      4 LABNXVOL       POINTER TO NEXT VOLID TO MOUNT
    004C   76 Address      4 LABVSECT       FORWARD CHAIN POINTER TO VOLSECT
    0050   80 Address      4 LABCSECT       VOLSECT ADDR OF CURRENT VOLID
    0054   84 Character  120 LABVOLS        SPACE FOR 15 ADDITIONAL VOLIDS
    00CC  204 Bitstring    4 LABEND         FENCE FOR END OF VOLIDS
    00D0  208 Character   44 LABFILID       FILE IDENTIFIER
    00FC  252 Character   17 LABSTRP        LAST 17 CHAR OF LABFILID
              00000022       LABSIZE        (*-LABSECT+7)/8 SIZE OF LABSECT
                                            IN DOUBLE WORDS

#### LABSECT Storage Layout

    *** LABSECT - Control Block in LABSECT
    *
    *     +---------------------------+---------------------------+
    *   0 |         LABNEXT           |         LABFCBPT          |
    *     +---------------------------+---------------------------+
    *   8 |                       LABFILE                         |
    *     +-------------------------------------------------------+
    *  10 |                                                       |
    *     =                        LABFID                         =
    *     |      +------+-----------------------------------------+
    *  20 |      |LABSEC|                LABVOLID                 |
    *     +------+------+-------------+---------------------------+
    *  28 |         LABVSEQ           |         LABFSEQ           |
    *     +---------------------------+-------------+-------------+
    *  30 |         LABGENN           |  LABGENV    |   (036)-    |
    *     +---------------------------+-------------+-------------+
    *  38 |         -LABCRD           |         LABEXD-           |
    *     +-------------+------+------+---------------------------+
    *  40 |   -(03C)    |:FLAG1|:FLAG2|         LABCUVOL          |
    *     +-------------+------+------+---------------------------+
    *  48 |         LABNXVOL          |         LABVSECT          |
    *     +---------------------------+---------------------------+
    *  50 |         LABCSECT          |                           |
    *     +---------------------------+                           |
    *  58 |                                                       |
    *     =                       LABVOLS                         =
    *     |                           +---------------------------+
    *  C8 |                           |          LABEND           |
    *     +---------------------------+---------------------------+
    *  D0 |                                                       |
    *     =                       LABFILID                        =
    *     |                           +---------------------------+
    *  F8 |                           |                           |
    *     +---------------------------+                           |
    *     |                       LABSTRP                         |
    *     |                                  +--------------------+
    *     |                                  | 10D
    *     +----------------------------------+
    *
    *** LABSECT - Control Block in LABSECT

#### LABSECT Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    LABCRD         0036
    LABCSECT       0050
    LABCUVOL       0044
    LABDCRD        0042 01
    LABDEXD        0043 80
    LABDFID        0042 80
    LABDFSEQ       0042 08
    LABDGENN       0042 04
    LABDGENV       0042 02
    LABDSEC        0042 40
    LABDVID        0042 20
    LABDVSEQ       0042 10
    LABEND         00CC
    LABEXD         003C
    LABFCBPT       0004
    LABFDEF        0043 04
    LABFID         0010
    LABFILE        0008
    LABFILID       00D0
    LABFLAG1       0042
    LABFLAG2       0043
    LABFSEQ        002C
    LABGENN        0030
    LABGENV        0034
    LABLBDSC       0043 10
    LABNEXT        0000
    LABNOCHG       0043 01
    LABNXVOL       0048
    LABPERM        0043 02
    LABSCRAT       0043 40
    LABSCRSP       0043 20
    LABSEC         0021
    LABSIZE        00FC 00000022
    LABSTRP        00FC
    LABVOLID       0022
    LABVOLS        0054
    LABVSECT       004C
    LABVSEQ        0028

This information is based on z/VM V4R4.0.
Last updated on 28 Jul 2003 at 08:15:53 EDT.
Copyright IBM Corporation, 1990, 2003