guru meditation number

A Commodore Amiga computer term.

If the operating system had an unrecoverable error, it would halt the machine and put the message, "Guru meditation number: 342" (or some other number). Rather than store all the error messages in limited ROMs, it left you (or your local Amiga guru) to look up the relevant text in a book.

Sorta the precursor to Windows' Blue Screen of Death.

The guru is still alive in the Amiga OSes that all Amiga Freaks of today use (except for the fact that the screen doesn't say guru, though). And they're still useful. Actually, if you want to code proper exception handlers, you can catch them before the guru occurs. Two classic guru number are $80000005 which indicates division by zero, and $80000004 which indicates improper memory addressing. The guru meditation is a black screen with a flashing red frame in the upper 25% of it. In the frame two lines of text are present saying something like
Software failure. Press left mouse button to continue
Error: 8000 0004 Task E856450
(I'll go home look through it one of these days.)
A funny feature about this is that waiting ten seconds or pressing the right mouse button actually also makes the Amiga continue (resetting, which has actually already happened when the guru screen appears)
Another thing worth mentioning is of course that some Amiga demos have effects that perfectly simulate a guru. It's always a good pisstaker at a demo party, as some people will always think that the coder of the production is a complete lamer, until they realize that the guru was a fake.

Legend has it that there was a special Guru Meditation Number in Kickstart 1.2 and 1.3. If Exec got really confused, you would see

48454C50

as the error number. You couldn't find this error number in any manual or wherever you usually looked up those things.

Now, you would not think anything strange or funny about this number until you converted two and two numbers from the error number to decimal and looked up their ASCII values.

48=H, 45=E, 4C=L, 50=P

HELP

Just goes to show the general whackiness of the Amiga team until the suits got the better of them.