Computer Dictionary of Information Technology

Flash Lights Impressively

(FLI) /FLY/ A joke assembly language instruction first documented in the late 1970s in "The Hackers Dictionary".

The FLI instruction was frequently referred to by engineers when minicomputers such as the DEC PDP-8, PDP-11 and some early microcomputers such as the IMSAI and Altair had dozens of front panel lights.

"When the computer is about to do some long I/O operation, stick in a FLI so the accountants won't think the machine has hung again."