Check out example codes for "#include <sys/time.h> int main() { timespec ts; // clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD clock_gettime(CLOCK_REALTIME, &ts); // Works on Linux }". It will help you in understanding the concepts better.

Code Example 1

#include <sys/time.h>

int main()
{
   timespec ts;
   // clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
   clock_gettime(CLOCK_REALTIME, &ts); // Works on Linux
}

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