The SORT-CONTROL special register is the name of an alphanumeric data item that is implicitly defined as:
01 SORT-CONTROL GLOBAL PICTURE X(160) VALUE “file name”.
where “file name” is the file name used by the sort as the source for additional sort/merge options.
When used in nested programs, this special register is implicitly defined with the global attribute in the outermost program.
You can specify the SORT-CONTROL special register in a function wherever an alphanumeric argument is allowed.
The SORT-CONTROL special register is not necessary for a successful sorting or merging operation.
The sort control file takes precedence over the SORT special registers.