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From: edlee@chinet.chi.il.us (Edward Lee)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Real Time
Message-ID: <1989Dec22.072124.7218@chinet.chi.il.us>
Date: 22 Dec 89 07:21:24 GMT
References: <1514@utkcs2.cs.utk.edu>
Reply-To: edlee@chinet.chi.il.us (Edward Lee)
Distribution: usa
Organization: Chinet - Chicago Public Access UNIX
Lines: 28

In article <1514@utkcs2.cs.utk.edu> wozniak@utkux1.utk.edu (Bryon Lape) writes:
>
>	Could someone please give me a good definition for real time
>processes.
>
>
>-bryon-

REAL-TIME PROGRAM. n.  A program that receives a stream of data from
an external source and processes, or acts on, a unit of data before
or just as another unit of data is received.

There is a large number of potential applications for real-time
programming, particularly for military purposes.  The original
sidewinder missile comes to mind.  Side-winding is a rather inefficient
way for a missile to travel, since the shortest path between two points
is a straight line.  Perhaps the original sidewinder had slower
software, hardware, or both.  Modern sidewinders probably process
incoming data in a manner closer to real time and thus travel more
efficient paths.  I believe that the first time I saw the "real time"
terminology was several years ago in advertisements in Aviation Week
for programmers familar with real-time applications.

A potential non-military, real-time application that comes to mind
is the reporting of changing stock prices with minimal delay.


-Ed L