Label

The system does not retain label type information for cataloged data sets; if the label type is not coded in the LABEL parameter for a cataloged data set, the system assumes SL.

For a data set on a direct access device, the system obtains the label type from the DD statement; the label type is not obtained from any other source referred to in the DD statement. Only two label types are valid for direct access devices: SL and SUL.

SL

Indicates that a data set has IBM® standard labels. If this subparameter is omitted, SL is the default.

Code only SL or SUL for data sets on direct access devices.

If the LABEL parameter is coded on a SYSCKEOV DD statement, code LABEL=(,SL).

SUL

Indicates that a data set has both IBM standard and user labels.

Code only SL or SUL for data sets on direct access devices.

Do not code SUL for partitioned or indexed sequential data sets.

AL

Indicates that a tape data set has ISO/ANSI Version 1 or ISO/ANSI/FIPS Version 3 labels.

If you specify AL for a tape generation data set for output, the ending .GnnnnVnn (where n=0 through 9) will not appear as part of the file identifier (data set name field) of the HDR1 label. Instead, the data is placed in the generation and version number fields of the HDR1 label.

AUL

Indicates that a tape data set has user labels and ISO/ANSI Version 1 or ISO/ANSI/FIPS Version 3 labels.

NSL

Indicates that a tape data set has nonstandard labels.

Before you code NSL, ensure that your installation has created and installed non-standard label processing routines, described in z/OS DFSMS Installation Exits.

NL

Indicates that a tape data set has no labels.

When retrieving two or more data sets from several NL or BLP tape volumes, concatenate the DD statements and repeat the LABEL parameter on each DD statement.

If you are processing ASCII data on unlabeled tapes, the data control block must specify OPTCD=Q.

BLP

Requests that the system bypass label processing for a tape data set.

If the installation did not specify the BLP feature in the reader cataloged procedure, BLP has the same effect as NL.

If you code BLP and the tape volume has labels, a tapemark delimits the data set. To let the system position a tape with labels to the proper data set, code the data-set-sequence-number subparameter; the number must reflect all labels and data sets that precede the desired data set.

Do not specify BLP when the DD DSNAME parameter requests all members of a generation data group (GDG); the system obtains the data-set-sequence-number from the catalog. Therefore, coding BLP might result in incorrect tape positioning.

When retrieving two or more data sets from several NL or BLP tape volumes, or when retrieving a data set from several BLP tape volumes and those volumes have labels, concatenate the DD statements and repeat the LABEL parameter on each DD statement.

LTM

Indicates that the data set has a leading tapemark.

Note: You may use the LABEL parameter when allocating a system-managed tape volume, but you cannot use the NSL or LTM subparameters. If the ACS routine does not exclude these subparameters, the job will fail with JCL errors.

System-managed tape volumes must be IBM standard label or ANSI standard tapes.