31 lines
1.9 KiB
Plaintext
31 lines
1.9 KiB
Plaintext
software rot
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n. Term used to describe the tendency of software that has not been used in
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a while to lose ; such failure may be semi-humorously ascribed to bit rot.
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More commonly, software rot strikes when a program's assumptions become out
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of date. If the design was insufficiently robust , this may cause it to fail
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in mysterious ways. Syn. code rot. See also link rot. For example, owing to
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endemic shortsightedness in the design of COBOL programs, a good number of
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them succumbed to software rot when their 2-digit year counters underwent
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wrap around at the beginning of the year 2000. Actually, related lossages
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often afflict centenarians who have to deal with computer software designed
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by unimaginative clods. One such incident became the focus of a minor public
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flap in 1990, when a gentleman born in 1889 applied for a driver's license
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renewal in Raleigh, North Carolina. The new system refused to issue the
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card, probably because with 2-digit years the ages 101 and 1 cannot be
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distinguished. Historical note: Software rot in an even funnier sense than
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the mythical one was a real problem on early research computers (e.g., the
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R1; see grind crank ). If a program that depended on a peculiar instruction
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hadn't been run in quite a while, the user might discover that the opcodes
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no longer did the same things they once did. ( Hey, so-and-so needs an
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instruction to do such-and-such. We can snarf this opcode, right? No one
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uses it. ) Another classic example of this sprang from the time an MIT
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hacker found a simple way to double the speed of the unconditional jump
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instruction on a PDP-6, so he patched the hardware. Unfortunately, this
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broke some fragile timing software in a music-playing program, throwing its
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output out of tune. This was fixed by adding a defensive initialization
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routine to compare the speed of a timing loop with the real-time clock; in
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other words, it figured out how fast the PDP-6 was that day, and corrected
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appropriately. Compare bit rot.
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