The total processtime is the sum of the user and system times, or 24.15 seconds for this example. Like cputime, computing etime requires subtracting its value before the code section from its value after the code section. Use of dtime does not require this subtraction. In addition, both dtime and etime use an array of length 2 for an argument. This argument contains a breakdown of the processtime into user and system times.
Clock returns a value in seconds and clockx returns a value in microseconds.