JCL sort is actually really easy to do. You simply just call the sort job, pass it the files, and tell it the parms on what type of sorting you want. For example, if you want your JCL to only include a certain condition of rows on input, just use the sample parms on your sysin as shown:
//SYSIN DD *
SORT FIELDS=COPY
INCLUDE COND=(41,3,CH,EQ,C'ABC') (This means you will include only the conditions where position 41, for 3 bytes, equals ABC). The include parameter can handle almost anything for extracting specifc rows from your input.

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