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33 * @(#)hertz.c 8.1 (Berkeley) 6/6/93
35 * $DragonFly: src/usr.bin/gprof/hertz.c,v 1.3 2003/10/04 22:36:45 hmp Exp $
41 * discover the tick frequency of the machine
42 * if something goes wrong, we return 0, an impossible hertz.
50 tim
.it_interval
.tv_sec
= 0;
51 tim
.it_interval
.tv_usec
= 1;
52 tim
.it_value
.tv_sec
= 0;
53 tim
.it_value
.tv_usec
= 0;
54 setitimer(ITIMER_REAL
, &tim
, 0);
55 setitimer(ITIMER_REAL
, 0, &tim
);
56 if (tim
.it_interval
.tv_usec
< 2)
58 return (1000000 / tim
.it_interval
.tv_usec
);