Boolean variables can have only two values: true and false. In CL, they are known as logical variables. In RPG, they’re called indicator variables. They’re not essential; I got by without them for years. But they are useful. Let’s take a closer look at Boolean variables.

Let me share a story with you. Some years ago, a certain factory started faxing requirements reports to their suppliers. The suppliers liked the reports, but some of them asked if they might receive the requirements electronically in a spreadsheet format. The IT department added a one-digit code to the database.

• 1=send by

Imagine needing to delete a large number–50, 100, 1,000–device descriptions, all of which begin with the same group of characters, from your system. Now imagine the Delete Device Description (DLTDEVD) command not accepting a generic device name. That got ugly quickly, didn’t it? And yet that sort of thing is what programmers often force end users to do. Maybe we need to add generic processing to our applications.

I have written about generic names before. (See Related Stories at the end of this article.) But I have not written about using generic values in the context of application development.

Suppose

Good article on the secrets of the IBM i IPL parameters. Is there a way to stop the system from restarting after my full system backups complete (GO SAVE, option 21)? There are times that it would be great for the system to stay in restricted state after a backup, but the startup CL program always runs. How do I stop it from running?

–Doug

Here’s the drill for changing your System i and Power i partitions so that they don’t kick off their system startup programs after a GO SAVE, option 21, full system backup.

First, realize that