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// rollover - emit dates across the 32-bit unix epoch rollover

#include <sys/types.h>

#include <limits.h>
#include <stdint.h>
#include <stdio.h>
#include <time.h>

char buf[80];

void
showtime(struct tm *tm)
{
	strftime(buf, 79, "%Y-%m-%d %H:%M:%S", tm);
	printf("%s\n", buf);
}

int
main(void)
{
	struct tm *when;
	// OpenBSD already has a 64-bit epoch counter so we instead
	// force the use of a 32-bit counter
	int32_t nau  = INT_MAX;
	time_t epoch = nau;

	when = gmtime(&epoch);
	showtime(when);

	nau++;
	epoch = nau;
	when  = gmtime(&epoch);
	showtime(when);

	return 0;
}