16. START-TBUOW (1 byte)

This field, start new unit of work for a VTS-TSR, must be set to S, in order for an application to continue to access the current generation of a VTS-TSR, if the generation for the VTS was changed while the application was accessing it. tableBASE reinitializes this field to low-values after every tableBASE command has completed.

The generation number of a VTS-TSR increases when the VTS is shut down and restarted or when a read-only VTS-TSR is switched to read-write or back to read-only mode. When this happens, unless this field is set to S, applications accessing the VTS will lose access due to the change in generation number. An error code of 1072-15 indicates that the generation number of the VTS being accessed has changed. Note that read-only VTS-TSRs are only available with the VTS Gate interface.

If any tableBASE command that accesses a VTS-TSR (commands that read or update a TSR), after its generation number has changed, is issued with this field set to S, all subsequent tableBASE commands which access a TSR will be able to continue accessing that generation of the VTS. If the first command issued does not actually access the VTS (for example, LV), access to the current generation of the VTS is not activated. Since tableBASE reinitializes the field after every command, the value of S will have to be resupplied on the next command that requires access to the current generation of the VTS, if this access has not been activated. Using S in this field is innocuous even if access to the current generation of the VTS has been activated so it can be set to S with every command, if desired.

This field is only applicable for VTS access where the VTS name is in the TB-SUBSYSTEM field of the TB-PARM parameter or where the VTS name is used as a linked list. It is not supported for VTS access where the VTS name is placed in the VTSNAME parameter.

See tableBASE command categories by TSR access for more information on commands that require access to a TSR.