ExtSM
The Callable Sort Module (ExtSM)  is a standalone sort routine that enables you to sort and re-order data files. Its call interface enables you to take advantage of alternative sort modules that are usually faster than the default run-time system sort module and provide greater flexibility in sorting data.
The main advantages provided by ExtSM are:
•	Use either quick sort or insertion sort techniques
•	Choose ascending or descending key ordering
•	Use an externally supplied collating sequence