Identifying free space with the POS command
To retrieve the area name and the next available position within the sequential dependent
part from all online areas, you can issue an unqualified POS command. This type of
command also retrieves the free space in the independent overflow and sequential dependent
parts.
After a successful unqualified
POS command, the I/O area contains the
length (LL) followed by the same number of entries as areas within the database. Each entry contains
field two through five shown below: - LL
- A 2-byte field containing the total length of the data in the I/O area, in binary. The length includes the 2 bytes for the LL field, plus 24 bytes for each entry.
- Area Name
- An 8-byte field giving the ddname from the AREA statement.
- Position
- An 8-byte field giving the next available position within the sequential dependent part.
- Unused CIs
- A 4-byte field containing the number of unused CIs in the sequential dependent part.
- Unused CIs
- A 4-byte field containing the number of unused CIs in the independent overflow part.