Easily measure elapsed time

Question

I am trying to use time() to measure various points of my program.

What I don\'t understand is why the values in the before and after are the same? I understand thi

Answer 1

time(NULL) returns the number of seconds elapsed since 01/01/1970 at 00:00 (the Epoch). So the difference between the two values is the number of seconds your processing took.

int t0 = time(NULL);
doSomthing();
doSomthingLong();
int t1 = time(NULL);

printf ("time = %d secs\n", t1 - t0);

You can get finer results with getttimeofday(), which return the current time in seconds, as time() does and also in microseconds.