Most sites have many applications involving sorting. DFSORT is often used by these applications either directly by invoking DFSORT with JCL, or indirectly by invoking DFSORT from a program. In particular, the COBOL SORT statement, and the PL/I sort routines result in calls to DFSORT (see the appropriate language documents for complete details).

The way in which COBOL interfaces with DFSORT depends on the use of COBOL features such as FASTSRT, NOFASTSRT, USING, GIVING and INPUT and OUTPUT PROCEDUREs, and DFSORT features such as COBOL exits and DFSORT control statements. In general, the features you use are dictated by the needs of your application. But in many cases, an application can achieve its results using one or another of these features, that is, you have a choice. This chapter describes some of the COBOL and DFSORT features you can choose and the performance and productivity implications of doing so.

See the appropriate COBOL guide if you are not familiar with any of the COBOL features described in this chapter. See z/OS DFSORT Application Programming Guide if you are not familiar with any of the DFSORT features described in this chapter. See z/OS DFSORT: Getting Started for tutorials on DFSORT control statements and features.