Access to permanent data objects

When you have access to a permanent data object, you can:

View the object through one or more windows — Depending on the object size and the window size, a single window can view all or part of a permanent object. If you define multiple windows, each window can view a different part of the object. For example, one window might view the first block of the permanent object and another window might view the second block. You can also have several windows view the same part of the object or have views in multiple windows overlap. For example, one window might view the first and second blocks of a data object while another window views the second and third blocks.
Change data that appears in a window — You can examine or change data that is in a window by using the same instructions you use to examine or change any other data in your program’s storage. These changes do not alter the object on DASD or in the scroll area.
Save interim changes in a scroll area — After changing data in a window, you can have window services save the changed blocks in a scroll area, if you have requested one. Window services replaces blocks in the scroll area with corresponding changed blocks from the window. Saving changes in the scroll area does not alter the object on DASD or alter data in the window.
Refresh a window or the scroll area — After you change data in a window or save changes in the scroll area, you may discover that you no longer need those changes. In that case, you can have window services refresh the changed data. To refresh the window or the scroll area, window services replaces changed data with data from the object as it appears on DASD.
Replace the view in a window — After you finish using data that is in a window, you can have window services replace the view in the window with a different view of the object. For example, if you are viewing the third, fourth, and fifth blocks of an object and are finished with those blocks, you might have window services replace that view with a view of the sixth, seventh, and eighth blocks.
Update the object on DASD — If you have changes available in a window or in the scroll area, you can save the changes on DASD. Window services replaces blocks on DASD with corresponding changed blocks from the window and the scroll area. Updating an object on DASD does not alter data in the window or in the scroll area.