Specifying the listing data set: SYSPRINT

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Define the data set that contains your listing output with the SYSPRINT DD statement: 
//SYSPRINT DD   SYSOUT=A

The assembler uses this data set to produce a listing. You can direct output to a printer, a magnetic tape, or a direct-access storage device. The assembler uses ASA or machine control characters for this data set according to the ASA option.