DALVLRDS indicates that the system is to obtain volume serial information from the specified cataloged data set. This key is mutually exclusive with the SYSOUT (DALSYSOU) and volume serial (DALVLSER) keys. (You cannot use a volume reference to a ddname for dynamic allocation.) For a given job step, the system allows a maximum of 1489 backward references (for a VOL=REF to a dsname or DCB=dsname) when the data set names are 44 characters long.
When you code this key, # must be one, LEN is the actual length of the dsname, and PARM contains the dsname (a name of all blanks is invalid).
KEY # LEN PARM
0014 0001 0004 C4 E2 D5 F1