Command Dataset (-@)

Use the Command Dataset execution command (-@) to specify a DDNAME defining a dataset that contains map names and execution commands. This command is unique to z/OS Batch. If this command is used, it can only appear in the PARM statement and it must be the only command coded in the parm statement (for example: EXEC PGM=DTXCMDSV,PARM='-@DTXPARM'). Using the command dataset eliminates the 100-byte limitation of the JCL PARM statement. Within the command dataset, map names and execution commands may be coded free-form. The command dataset may reside on disk or it may be defined instream in the JCL. If defined instream, ensure that there are no sequence numbers in columns 73 through 80. A sequence number, because it does not begin with the switch indicator (- or /), is interpreted by the command parsing logic as a map name.

-@ddname