Recursion and the Alternatives

March 9, 2005 Ted Holt

The code for this article is available for download.

Recursion is usually defined as the ability of a process (a program, a subprocedure, and so forth) to call itself. It is a fun topic to write about and a fun technique to use in programming. Recursion often simplifies the effort required to code a task in a computer language. However, recursion is not without its drawbacks. In this article, I hope to help readers determine when recursion is appropriate and to suggest alternatives to use when recursion is not suitable.

An Example of Recursion

To illustrate the concepts that

PC5250 and the Print Key

March 9, 2005 Hey, Ted

I have a tip for your newsletter. For ages, I have always used the PrtScrn button from a Client Access PC5250 terminal emulation session to print the contents of a display on my local network printer. Recently, I needed the screen contents to go to an output queue instead, as would occur when I would press the Print key on dumb terminals in ages past. It took a while, but I found the key sequence for the Print key.

To send the contents of a display screen to an output queue, use Control NumLock. I could not find this information

Admin Alert: Creating a Save Changed Objects

March 9, 2005 Joe Hertvik

Backup Tape

Like most operating systems, OS/400 provides a save changed objects function, allowing you to selectively backup only those objects that have changed since the last full system backup. This week, I’ll examine the save changed objects procedure and give you some simple CL code for creating a saved objects backup tape. A save changed object backup works in conjunction with a full system backup to minimize weekly backup times and to enable administrators to restore objects from several different tapes in a backup cycle.

The two backups work together in the following way:

• The full system or Save