The upcoming Y2038 catastrophe

[bob]

Here we have one caught in the wild:

bobo.c:

Code: Select all

#include <stdio.h>
#include <time.h>
#include <sys/time.h>  

int main(void)
{
        struct timeval tv1, tv2;   

        gettimeofday(&tv2, NULL);
        do {
                tv1 = tv2;

                gettimeofday(&tv2, NULL);
        } while((tv1.tv_sec < tv2.tv_sec) ||
                ((tv1.tv_sec == tv2.tv_sec) && (tv1.tv_usec <= tv2.tv_usec)));

        printf("tv1: %ld %d\n", tv1.tv_sec, tv1.tv_usec);
        printf("tv2: %ld %d\n", tv2.tv_sec, tv2.tv_usec);

        return 0;
}

Output:

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tv1: 1412665030 366901
tv2: 1412665029 267027

System log:

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7 Oct '14 8:57:09.268 AM ntpd[131]: ntpd: wake time set -1.099871 s

Nobody was near the computer when this happened, as I had just left a couple of minutes earlier. Last reboot was 3 days before.

Across a sleep/wake-up anything can happen. Just as it can across a reboot or anything else that violently stops the CPU so that ntpd can't continue to run and keep the clock current. Macs are absolutely notorious for doing that. I disabled it on my office machine since I use it to play on ICC automatically all the time. When it sleeps, it is unreachable from the network. Mine no longer sleeps.