DD Statement - temporary data set narrative
DSN=
For temporary data sets used solely within the same job step, there is no need to provide a data set name as the system will
create one, using a combination of sequence number, date and time.
UNIT=
The UNIT= operand is mandatory, unless SMS is managing temporary data sets.
This allocates a device(s) on which the data set is to be placed. SYSDA is a common IBM supplied generic name typically
associated with a pool of disks.
Whilst it is possible to allocate specific units, it is best practice to specify a generic type, such as SYSDA mentioned above,
to aid availability and throughput. Generic names can be either IBM or System Programmer defined.
SPACE=
Unlike on a PC, new disks data sets require an indication of the amount of physical space they will occupy. This traditional
example indicates that the space must not be segmented (CONTIG), and it will be allocated in CYLinders which are 15 times
larger than tracks (TRKS). Too little space results in an x37 ABEND.