Around the year 1975 I learned to use the UNIVAC 1100 time-sharing mainframe computer, which made available to the user 128K of memory. If you stayed on too long without doing anything, the computer would close you out. Computer time was expensive in those days, and there was chargeback for time used. I learned however, that there was a program – @FARBLE – which fooled the computer and allowed you to stay on longer. The capital letters are due to the fact that this computer usually worked with capitals only, although it could be forced to learn small letters too. When I learned about @FARBLE I was not told that you had to leave the program you were running first. If you failed to do so, it would get into a loop, and this was especially liable to occur if you were running a program written in the SPITBOL programming language. Late one evening, I tried to use @FARBLE and of course the program started spitting out all kinds of garbage. I called my programmer, but he was not available. I tried everything I knew to rein in the machine, but nothing worked. Eventually in despair I turned off the terminal, and went home to bed.
Early next morning I returned, and switched on the machine. The program had apparently stopped, and there was a message: MAX PAGES. I called up my programmer and told him what had happened. He began to giggle. But when I told him about MAX PAGES, the giggling stopped, and there was an audible gulp. "MAX PAGES?" he said. "MAX PAGES??? Nobody EVER reaches MAX PAGES!" Well, I was the nobody who did. The computer had run all night, using up $4767.21 of computer time at the special night-time rate which was 10% of normal.
He then told me what I should have done to end the program run amuck. I should have entered @@X TIO which would have stopped the program and discarded the output. Of course that command would have been a little difficult to guess, but I was able to use it again quite soon. A couple of weeks later I was sitting at a machine, when a student sitting next to me by accident entered an unpublished code which started spitting out the names of all the files on the system. He yelled and looked horrified. "What can I do?" he said pleadingly. With aplomb I leaned over, typed in @@X TIO, and the machine obediently declared that the program had been halted. "Thank you so much," he said. "You're welcome," I said.
I only meant to FARBLE,
And save a buck or two,
But sure enough you looped the loop,
And ran the whole night through!I only meant to FARBLE,
And take a spot of tea,
But you kept right on going –
And almost spent 5G.I didn't mean to garble,
Or set your bits awry.
No order could restrain you,
You SPITBOLed in my eye.You really would not listen,
You laughed at @@TERM,
You wouldn't take an EXIT,
You really made me squirm.And now the Dean is puzzled –
Perhaps a bit impressed –
"My, what a lot of lolly
On *DICT to invest."I've dreamed of living grandly,
And spending like a sheik –
How strange that I should do it
When I was not awake!