16.20 - Changing the Value for Locate-mode - Teradata Tools and Utilities

Teradata® Call-Level Interface Version 2 Reference for Mainframe-Attached Systems

Teradata Tools and Utilities
September 2019
Programming Reference
Locate-mode is initialized by DBCHINI to the default value provided for Locate-mode in the HSHSPB. When the value for Locate-mode is not appropriate for an application, perform the following procedure before calling DBCHCL for Connect, RunStartUp, Command, or Initiate Request functions:
  1. Set Change-options to 'Y'.
  2. Change the value for Locate-mode as follows.
    If the data returned is to be... Then change the value for Locate-mode to...
    made available in the response buffer Y
    made available in the move area N
  3. Use mnemonics for the codes. Mnemonics are provided in the language definition file for the DBCAREA.

    Within this manual, the following conventions apply:

    • Locate-mode of Y is known as Locate-mode.

    • Locate-mode of N with Parcel-mode-fetch of Y is known as Move Mode.

Locate-mode operates in conjunction with Parcel-mode-fetch. The setting of Locate-mode affects the use of Fetch-maximum-data-length, Fetch-data-pointer, Fetch-returned-data-length, and Fetch-parcel-flavor.

Varying-length-fetch and Locate-mode can be set to 'Y' at the same time.

When using Locate-mode, applications should not change the data whose pointer is returned. This data resides in the response buffer allocated and controlled by CLIv2 and altering it may impact CLIv2 in unpredictable ways. Locate-mode is provided as a performance option for applications that need only inspect the data. Performance is improved by not copying the data to the application's storage. But if the data must be modified, Locate-mode should not be used.