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- #include <stdio.h>
- #include <stdlib.h>
- #include <sys/time.h>
- #define OVERHEAD_TIMES 30000
- int main(int argc, char** argv, char** envp) {
- struct timeval tv;
- gettimeofday(&tv, NULL);
- if (argc < 2)
- return -1;
- unsigned long long msec1 = atoll(argv[1]);
- unsigned long long msec2 = tv.tv_sec * 1000000ULL + tv.tv_usec;
- struct timeval tv1, tv2;
- gettimeofday(&tv1, NULL);
- for (int j = 0; j < OVERHEAD_TIMES; j++) {
- gettimeofday(&tv, NULL);
- }
- gettimeofday(&tv2, NULL);
- unsigned long long msec3 = tv1.tv_sec * 1000000ULL + tv1.tv_usec;
- unsigned long long msec4 = tv2.tv_sec * 1000000ULL + tv2.tv_usec;
- unsigned long long overhead = (msec4 - msec3) / OVERHEAD_TIMES;
- printf("%llu\n", msec2 - msec1 - overhead);
- return 0;
- }
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