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You've Got 25 Years Until UNIX Time Overflows

Posted by timothy on from the start-packing dept.

CowboyRobot writes "In 25 years, an odd thing will happen to some of the no doubt very large number of computing devices in our world: an old, well-known and well-understood bug will cause their calculation of time to fail. The problem springs from the use of a 32-bit signed integer to store a time value, as a number of seconds since 00:00:00 UTC on Thursday, 1 January 1970, a practice begun in early UNIX systems with the standard C library data structure time_t. On January 19, 2038, at 03:14:08 UTC that integer will overflow. It's not difficult to come up with cases where the problem could be real today. Imagine a mortgage amortization program projecting payments out into the future for a 30-year mortgage. Or imagine those phony programs politicians use to project government expenditures, or demographic software, and so on. It's too early for panic, but those of us in the early parts of their careers will be the ones who have to deal with the problem."

7 of 492 comments (clear)

  1. Could we be a little less biased? by damn_registrars · · Score: 5, Insightful

    those phony programs politicians use to project government expenditures

    The programs are real, even if the math may be phony.

    --
    Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
    1. Re:Could we be a little less biased? by Anonymous Coward · · Score: 5, Insightful

      History shows us that it's not biased in the slightest to assume that politicians will lie, cheat, and steal their way to riches. Giving them the benefit of the doubt is like Charlie Brown giving that field goal one more shot because maybe, just maybe, Lucy won't pull the ball this time.

    2. Re:Could we be a little less biased? by InterGuru · · Score: 5, Insightful

      We denigrate politicians because they lie, but candidates who tell the truth do not get elected.

  2. Mortgage Calculations by bill_mcgonigle · · Score: 5, Insightful

    Was this a USENET post from '94? Mortgage systems using 32-bit time_t (if there ever were any) failed 5 years ago for 30-year mortgages. We did not hear an earth-shattering kaboom.

    --
    My God, it's Full of Source!
    OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
  3. Re:64-bit computers DO NOT solve this problem by locofungus · · Score: 5, Insightful

    Compiling away isn't always that simple.

    You'd be amazed how many people code depending on the fact that sizeof(long) == sizeof(int) == sizeof(void*) == sizeof(time_t) == 4 even when they don't need to and structures are often mapped directly onto binary data, either from disk or network.

    I don't actually imagine that 2038 will be much of a problem - most of the issues that will be triggered by the above assumptions will occur between now and then and will be fixed as they occur.

    Then 2038 will loom and there will be a big drive to fix everything (else), the magic time will occur and there will be little more than a whimper. Then everyone will complain about the hype about a non-existent problem.

    I am quite looking forward to having the option of some lucrative consulting income in my early retirement should I decide I need it. :-)

    Tim.

    --
    God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
  4. Re:Not NetBSD by dingen · · Score: 5, Insightful

    The problem is not so much in computers still being 32 bits in 25 years time, but 32 bit computers right now doing calculations involving dates 25 years in the future.

    --
    Pretty good is actually pretty bad.
  5. Re:64-bit computers DO NOT solve this problem by Anonymous Coward · · Score: 5, Insightful

    $0.5M to be air-tight sure that a simple 20 lines of Pascal code doesn't crash one (or more) of the hundreds of A-10s in active service, each one worth $12+M, not to mention keeping those pilots safe.

    Yes. Definitely our government dollars at work.