User Exit Reference › USREXIT3 User Exit › Definitions

Definitions

A(VM userid)

Indicates the address of the user ID requesting the mount. If the mount is part of a CA VM:Batch job, it is the address of the user ID submitting the job. This field is padded on the right with blanks, that is, it is left-justified.

Following user ID is an 80-byte work area that you can use to pass information between exits. Note that this area is used by the Bin system exits BINEXIT3 and BINACNT. Be sure these areas are not overlaid if using the Bin system.

A(VM userid account number)

Indicates the address of the eight-byte account number obtained from the VMBLOK or ACCTBLOK of the user ID issuing the mount. Also, if the mount is part of a CA VM:Batch job, it is the account number of the user submitting the CA VM:Batch job.

A(TMC record for requested volser)

Indicates the address of the 340-byte TMC record for the volser that is being mounted. The file TMRECORD COPY on the VMTAPE 192 minidisk describes the format of this record. Use it to access various fields in the record. Because this exit is called before the TMC record has been updated, the TMC record contains the values from the previous mount or update, and does not include any information about the current mount.

If Autopick is enabled, this value will reflect a temporary saved status; the volser is owned by the CA VM:Tape server.

A(First and second tape record)

Indicates the address of the first 160 bytes read from the tape mounted by the operator. For standard label tapes, the first 80 bytes is the VOL1 record and the second 80 bytes is the HDR1 record. The HDR1 record can be used to perform data set name verification.

Note: Tapes written on a 36-track tape drive cannot be read by 18-track tape drives. Therefore, if the tape mounted by the operator was previously written on a 36-track drive and is now mounted on an 18-track drive, the first 80 bytes is the VOL1 record that was generated from the VOLID mark written by the 36-track drive. The second 80 bytes is initialized to HEX zeroes.

A(Character string: SL, NSL, NL, BLP, or AL)

Indicates the address of a character string indicating the label processing for the mount. This character string is three bytes long and padded with blanks on the right; that is, it is left-justified. The values can be SL for standard label tapes, NSL for nonstandard label tapes, NL for non-labeled tapes, BLP for bypass label processing and AL for ASCII labeled tapes.

A(Character string: R/O or R/W)

Indicates the address of a character string indicating the access type for the mount. This character string is three bytes long. The values can be R/W for read/write mounts and R/O for read/only mounts.

A(Common User Exit Buffer)

Indicates the address of the 256-byte work area to be used for passing information between the various user exits. This work area is specific to each command being processed by CA VM:Tape and cannot be used across commands.

A(Dataset Name)

Indicates the address of the 44 byte Dataset Name for this MOUNT request.

A(MOUNT Control Block Flags)

Indicates the address of the internal MOUNT Control Block Flags for this MOUNT request.

Important! **Do not alter the value of these flags in any way!!!** Each flag field may have multiple flag values set so a TM instruction should be used to test for any specific condition.