MPE/iX, the 3000's operating system, brims with elegant solutions that sometimes elude even long-time users of HP 3000s. Since the 3000 runs at its heart with a character-based interface, some of the elegance can only be tapped from the command line.
Walter Murray used to work for HP in its 3000 COBOL labs when the vendor actually had such things. Today the COBOL maintenance is minimal inside HP, and Murray works outside of HP's labs. He posted a reminder about a command-line trick that says a lot about the 3000 experience — and a little bit about who's left to keep the lamp of knowledge about the server lit.
Murray wanted to point out, late on a Saturday night over the weekend, that Control-X was still inside your 3000, waiting to be used. And if you're a customer who uses the command line, then Control-X can save you some keystrokes. Now Control-X is part of a terminal emulator for the 3000 too, Murray said:
I don’t know if anyone else even cares about this feature, but I’ve used it since the earliest days of MPE. When you’ve started to type a command or a line of input, and realize that you don’t really want to send that line, you can, of course, backspace over the entire line.
But the right way to handle this is to type a CNTL-X (line cancel) character. The terminal driver puts out three exclamation marks and a CR-LF, and ignores everything on that line.
Maybe everybody knows that, but I’ve run into a number of HP 3000 users who aren’t aware of it, especially in shops that use the Minisoft terminal emulator. Searching the archives, I found that this was discussed about five years ago, but apparently Minisoft did not release a fix.
Good news! I brought this to their attention, and the current release of the Minisoft 92 terminal emulator now handles CNTL-X. I just thought you would like to know.
The Internet and the Web changes the formula for figuring a system's lifespan. During the last decade, a computer abandoned by its maker would survive only as a hobbyist's workbench after five years or more. Now, the wisdom wired into a system like the 3000's, with a living community, can be timeless. On a weekend night a tip can emerge that the experts knew long before you started using your 3000. A vendor who's making an emulator like Minisoft can be convinced by a user to mimic this tip — even though the computer hasn't been sold as a new machine for nearly two years. It's all enough to make you start to question the meaning of the words "dead" and "old."
Our thanks for Murray for pointing out the tip on the 3000 mailing list, which has a new Web interface for customers who want to read or research MPE/iX expertise, but don't want to manage any more e-mail. More on that tomorrow.