help with timer

[msoh]

Hello,

i have the code below:

#include <sys/time.h>
#include <iostream>

using namespace std;

int main(void){
        struct timeval start, end;
	long differ;

	gettimeofday(&start, NULL); 	//start time.
	
	do_some_work();

	differ = end.tv_usec - start.tv_usec;	//elapsed time.
        cout << "\n\nelapsed time is " << differ;

        return 0;
}

i would like to ask the differ is in microseconds or milliseconds ?

Thanks.

[VictorN]

The short answer is: neither in microseconds nor milliseconds.
How is the operator -() defined for struct timeval? I guess it is not defined at all!
So, the result of your subtraction is not defined either!

Besides, you did not initialized the end variable, so how do you expect to use it?

[msoh]

OK, thanks