DMSTVS Exit

This section contains example EXECs set up using DMSTVS with REXX. The CMS program MOVEFILE is used in the EXECs to read and write data sets and files, but you can use any program that invokes OS simulation macros.

With DMSTVS, you must pre-mount the first tape you are going to use in the simulation. You can pre-mount the tape using the CA VM:Tape MOUNT command. DMSTVS can pass the data set name and the APASS, RPASS, WPASS, EXPDT, and RETPD options on the MOUNT command to all tapes for read/write mounts. However, any other options you specify on the MOUNT command affect only the first tape mounted.

You can also pre-mount the first tape using the CA VM:Tape SLMOUNT EXEC. The SLMOUNT EXEC also runs the CMS FILEDEF and LABELDEF commands for you using information you supply.

Note: For more information, see SLMOUNT EXEC.

If a read/write mount of any tape in the sequence other than the first tape fails, your application is notified and your program regains control. However, if such a mount fails in read-only mode, your application is presented with a premature end-of-file, which you may be unable to detect.

CA VM:Tape creates the DMSTVS exit as you enter the CA VM:Tape MOUNT command. CA VM:Tape loads the VMTTVS MODULE exit into storage and names it DMSTVS. To check whether VMTTVS MODULE exists, enter the following command:

listfile  vmttvs  module *

If VMTTVS MODULE exists, issue the following command:

listfile  dmstvi  module *

If you receive the following error message, you can use DMSTVS:

DMSLST002E FILE NOT FOUND. RC=28

Note: If file DMSTVI MODULE is found, CA VM:Tape will use the DMSTVI exit instead of the DMSTVS exit. To circumvent this behavior you can issue the CMS command SET TVICALL OFF.