Volume Access Exit

The volume access exit is entered during open or EOV if a volume is not RACF-protected and the accessibility field in the volume label contains:

an ASCII uppercase letter from A through Z for Version 3 tapes or
an ASCII uppercase letter from A through Z, a numeric 0 through 9, or special characters !*"%&'()+,-./:;<=>?_ for Version 4 tapes.

The exit is bypassed if security checking has been suppressed (as indicated in the Program Properties Table).

The exit can accept or reject the volume and can suppress label validation, issuing one of these return codes:

Return Code: Description
X'00': Use volume
X'04': Reject volume (set by IBM-supplied exit)

Suppress label validation by setting the high-order bit of the return code in the field named CONTROL in the source module ANSIEXIT (for example, a return code of 80 would indicate to use the volume and suppress validation). This bit is acted on every time the exit returns to the system.

The volume access exit is used only when the label validation suppression exit is not used.