I have a program in C which has to execute a series of another programs. I need to get the execution time of each of these programs, in order to create a log of these times.
I though of using system() to run each program, but I don't know how to get the execution time. Is there any way to do this?
The programs are "quick", so I need more precision than seconds.
You have at least 4 ways to do it.
A start point:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main ( void )
{
clock_t start = clock();
system("Test.exe");
printf ("%f\n seconds", ((double)clock() - start) / CLOCKS_PER_SEC);
return 0;
}
If you are in Windows and you have access to Window APIs you can use GetTickCount() too:
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
int main ( void )
{
DWORD t1 = GetTickCount();
system("Test.exe");
DWORD t2 = GetTickCount();
printf ("%i\n milisecs", t2-t1);
return 0;
}
And the best is
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
int main(void)
{
LARGE_INTEGER frequency;
LARGE_INTEGER start;
LARGE_INTEGER end;
double interval;
QueryPerformanceFrequency(&frequency);
QueryPerformanceCounter(&start);
system("calc.exe");
QueryPerformanceCounter(&end);
interval = (double) (end.QuadPart - start.QuadPart) / frequency.QuadPart;
printf("%f\n", interval);
return 0;
}
Question is tagged as C but for sake of completeness, I want add C++11 feature:
int main()
{
auto t1 = std::chrono::high_resolution_clock::now();
system("calc.exe");
auto t2 = std::chrono::high_resolution_clock::now();
auto x = std::chrono::duration_cast<std::chrono::nanoseconds>(t2-t1).count();
cout << x << endl;
}
clock() thing shouldn't work. clock() is supposed to return the best approximation to the CPU time used by the programme, it shouldn't count the time used by a system()-invoked programme (and it doesn't here, may be different on Windows). start = clock(); // get number of ticks before loop
/*
Your Program
*/
stop = clock(); // get number of ticks after loop
duration = ( double ) (stop - start ) / CLOCKS_PER_SEC;
