DFSORT interface description

Typically, an implicit enclave boundary occurs when an application issues an SVC LINK. However, this is not the case when DFSORT is invoked directly; that is, Language Environment will create a new enclave for DFSORT. To simplify calls to DFSORT, Language Environment concentrates the logic of the DFSORT invocation into the Language Environment service CEE3SRT.

When CEE3SRT is invoked, the routine acquires a new stack frame and some flags are set to indicate DFSORT invocation. As a result, the path length is slightly longer than if your application used LINK SVC to invoke DFSORT directly. However, when you invoke CEE3SRT, the routine also establishes exit DSAs and calls DFSORT using defined interfaces, which are described in the z/OS DFSORT Application Programming Guide.

Language Environment supports the DFSORT extended parameter list, which allows parameters to be placed above the 16M line. DFSORT Version 1 Release 1.1 or later is required for extended parameter list support.