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cbusy-waitingcpu-time

How can I write a C program to execute for a certain number of processor seconds?

I need a C program that would execute for a precise number of CPU seconds passed in as a parameter. I need such a program in order to test code that monitors a process' CPU usage.

Example:

busywait x

Should run for x seconds on my processor.

Solution

  • This is the C program I wrote to solve my problem. It continuously checks the number of clock cycles until the correct number of processor-seconds has been used.

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

int main(int argc, char * argv[])
{
     clock_t start, end;
     double cpu_time_used;
     int wait;

     sscanf(argv[1], "%d", &wait);

     start = clock();
     end = clock();
     while (((double) (end - start)) / CLOCKS_PER_SEC < wait)
     {
          end = clock();
     }
}