Creating a sequential data set

The next panel you see allows you to specify an action and a data set name. Because you want to allocate a new data set, type A on the OPTION line. Then specify the three data set qualifiers in the three ISPF LIBRARY fields.

-------------------------------  DATA SET UTILITY  -----------------------------
OPTION ===> a

    A - Allocate new data set                 C - Catalog data set
    R - Rename entire data set                U - Uncatalog data set
    D - Delete entire data set                S - Data set information (short)
    blank - Data set information

ISPF LIBRARY:
    PROJECT ===>  prefix
    GROUP   ===>  test
    TYPE    ===>  data

OTHER PARTITIONED OR SEQUENTIAL DATA SET:
    DATA SET NAME ===>
    VOLUME SERIAL ===>          (If not cataloged, required for option "C")

DATA SET PASSWORD ===>          (If password protected)

When you press the Enter key, you see a panel with a column of input fields that specify the details of allocating a data set. When you finish typing information in the fields, press the Enter key to create the data set.

Allocate New Data Set

----------------------------  ALLOCATE NEW DATA SET  ---------------------------
COMMAND ===>

DATA SET NAME:  PREFIX.TEST.DATA

   VOLUME SERIAL     ===>                (Blank for authorized default volume)*
   GENERIC UNIT      ===>                (Generic group name or unit address)*
   SPACE UNITS       ===> blks           (BLKS, TRKS or CYLS)
   PRIMARY QUAN      ===> 20             (in above units)
   SECONDARY QUAN    ===> 10             (in above units)
   DIRECTORY BLOCKS  ===> 0              (0 for sequential data set)
   RECORD FORMAT     ===> FB
   RECORD LENGTH     ===> 80
   BLOCK SIZE        ===> 800
   EXPIRATION DATE   ===>                (YY/MM/DD
                                          YY.DDD in Julian form
                                          DDDD for retention period in days
                                          or blank)


   ( * Only one of these fields may be specified)

The previous panel shows an example of values for creating a sequential data set. However, you might want to find out the values your installation recommends.

Basically the fields on the Allocate New Data Set panel determine data set attributes, such as:

On which storage device the data set goes (VOLUME SERIAL, GENERIC UNIT). You can leave these fields blank.
Size of the space (SPACE UNITS, PRIMARY QUANTITY, SECONDARY QUANTITY).
The amount of space needed for a PDS directory (DIRECTORY BLOCKS). The general rule is one directory block for every six members.
The kind of records you want in the data set (RECORD FORMAT, RECORD LENGTH, BLOCK SIZE).
How long you want to keep the data set (EXPIRATION DATE). You may leave this field blank.

For more information about these fields, press the HELP PF key (PF 1) while the Allocate New Data Set panel is displayed, or see z/OS TSO/E User's Guide.

Note: When you display the Allocate New Data Set panel, the fields generally show the values from the previous allocation. If you want to allocate a data set with the same attributes as an existing data set, specify the existing data set name on the Data Set Utility panel and leave the OPTION line blank. After the data set information is displayed for the existing data set, you can return to the Data Set Utility panel, specify the new data set name, enter A on the OPTION line, and the correct attributes appear on the Allocate New Data Set panel.

Exercise
Create a sequential data set by following the example starting at Creating a data set in ISPF/PDF. When you press the Enter key on the last panel, your data set is created and you see in the upper right-hand corner of the panel, the message: `DATA SET ALLOCATED`