std::difftime

 

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Defined in header <ctime>
double difftime( time_t time2, time_t time1 );

Computes difference between two calendar times as time_t objects (time2 - time1) in seconds.

Parameters

time1, time2

-

times to compare

Return value

Difference between two times in seconds

Example

#include <iostream>
#include <ctime>
int main()
{
    std::time_t start = std::time(NULL);
    volatile double d;
    for(int n=0; n<10000; ++n)
       for(int m=0; m<100000; ++m)
           d += d*n*m; // some time-consuming operation
    std::cout << "Wall time passed: "
              << std::difftime(std::time(NULL), start) << " s.\n";
}

Output:

Wall time passed: 7 s.

See also

duration (C++11)	a time interval (class template)
C documentation for difftime