1. [techspeak] adj. Describes an application which requires a program to respond to stimuli within some small upper limit of response time (typically milli- or microseconds). Process control at a chemical plant is the canonical example. Such applications often require special operating systems (because everything else must take a back seat to response time) and speed-tuned hardware.
2. adv. In jargon, refers to
doing something while people are watching or waiting. I asked her
how to find the calling procedure's program counter on the stack and she
came up with an algorithm in real time.