Overview CHKDSN – Check for DSN Utility for MVS 3.8J TSO / ISPF / Hercules(current version 1.0.02  2024-07-01) Sometimes it is necessary to immediately (in real-time) determine if a dataset (DSN) exists, whether on the system catalog and VTOC or VTOC only. In other words, check for the presence of a cataloged or uncataloged DSN. Under TSO, the SYSDSN function … Continue reading CHKDSN in MVS38J