Return difference between two times.
  Calculates the time difference between timer1 and timer2 in seconds.

Parameters.

timer2

Latter time

timer1

Former time

Return Value.
  The difference in seconds between the two times specified.

Portability.
  Defined in ANSI-C.

Example.

/* difftime example */
#include <stdio.h>
#include <time.h>

int main ()
{
  time_t start,end;
  char szInput [256];
  double dif;

  time (&start);
  printf ("Please, enter your name: ");
  gets (szInput);
  time (&end);
  dif = difftime (end,start);
  printf ("Hi %s.\n", szInput);
  printf ("You have taken %.2lf seconds to type your name.\n", dif );
 
  return 0;
}

See also.
  asctime, gmtime, localtime, time