UCB= rs-type or (2-12) standard form UCB= rx-type or (2-12) execute form

Specifies the address of the UCB for the VTOC to be accessed. The UCB address might be for a captured UCB, or for an actual UCB above or below the 16 MB line. Use the address of a UCB, not a UCB copy. An unauthorized caller must not use this parameter. If your program is in 31-bit mode, this address must be in 31-bit address; the high order byte is part of the address. You should not code the UCB parameter with MF=L.

DEB=addr or (reg)

Supplies the address of a DEB opened to the VTOC you want to access. If you are not authorized, specify a DEB address, not a UCB, to CVAFFILT; also, without authorization, you cannot perform any asynchronous activity against the data set represented by the DEB (such as EXCP, CLOSE, EOV), because CVAF removes the DEB from the DEB table for the duration of the CVAF call. See Identifying the Volume for further details.

If you supply a previously obtained I/O area through the IOAREA keyword, neither UCB nor DEB is needed. Otherwise, supply either a UCB or DEB. If you supply a UCB address, it is overlaid in the CVPL by the UCB address in the I/O area. If you supply both the UCB and the DEB addresses in the CVPL, the DEB address is used and the UCB address in the CVPL is overlaid by the UCB address in the DEB.