57 lines
3.0 KiB
Plaintext
57 lines
3.0 KiB
Plaintext
|
|
DRIP Version 2.00
|
|
Release Package
|
|
|
|
DRIP is a program intended solely for its entertainment value, generally
|
|
derived from running the program surreptitiously on another person's
|
|
machine.
|
|
|
|
When DRIP runs, it produces no messages or other signs of its activity,
|
|
installing itself inline with INT 8, the clock interrupt. It remains
|
|
totally dormant until SCROLL LOCK is depressed, then remaining active
|
|
until SCROLL LOCK is depressed again. When active, each time the clock
|
|
interrupt executes (about every 1/22 second), it decrements a timer
|
|
value which is a pseusdorandom value of varying maximum limit to see if
|
|
it DRIP is due to run. If so, it examines the screen memory to locate a
|
|
character on the screen which has free space beneath it. That character
|
|
is moved downscreen until it either falls off the screen entirely, or
|
|
encounters another character in its fall and comes to rest over it.
|
|
The result is that randomly selected characters on the screen appear
|
|
to 'fall off the screen'.
|
|
|
|
The interval between activations of the program is a pseudorandom function
|
|
with a maximum value which decreases by a half every 64 characters moved, so
|
|
that by the time a few hundred characters have been moved, it is running
|
|
reasonably continuously.
|
|
|
|
DRIP is capable of moving one character on the screen at a time. However,
|
|
for a variation, DRIP may be run more than once, installing a copy of itself
|
|
each time it is run. The result is that there will be a maximum number of
|
|
simultaneously moving characters equal to the number of installed copies.
|
|
|
|
DRIP is totally transparent to any running programs (except, perhaps the
|
|
few that mess around with the clock interrupt). It has no effect
|
|
whatever on the running system when not activated, and minimal effect
|
|
(a slight execution time burden on the clock interrupt) when it is
|
|
active. It has been tested on CORONA, COMPAQ, and IBM machines, including
|
|
various video cards and modes. The only objectionable effect seen to date
|
|
is slight screen 'snow' during the burst of screen ram activity when
|
|
DRIP is hunting for a character to move when it runs, this occuring
|
|
on some inexpensive display adaptors. Most machines' displays
|
|
handled the activities of DRIP without complaint.
|
|
|
|
DRIP was written and is released as a generalized giggle for the PC
|
|
user community. It may be freely copied and distributed for its intended
|
|
purpose. UNDER NO CIRCUMSTANCES SHOULD MODIFICATIONS BE MADE TO DRIP
|
|
AND THE RESULT RELEASED TO OTHERS, NOR MAY DRIP BE SOLD FOR PROFIT.
|
|
Every effort has been undertaken to produce and release a fully
|
|
debugged and safe program. It has been carefull written and extensively
|
|
tested. However, the final responsibility is up to the user to ensure
|
|
that DRIP runs correctly with particular programs, and to ensure that
|
|
his copy of DRIP is itself intact. The author assumes no responsibility
|
|
for consequences arising from the use of DRIP.
|
|
|
|
G. Masters May, 1987 Thousand Oaks, CA
|
|
|
|
<end of document>
|
|
|