#include <sys/time.h>
 
/* prototypes */

void StartCronograph();

float ElapsedTime();
 
struct timeval tpi;

/* implementations */

void StartCronograph()
{
  gettimeofday( &tpi, NULL );
/*
  printf("Sec = %ld, microsec = %ld\n", tpi.tv_sec, tpi.tv_usec );
*/
}
 
float ElapsedTime()
{
  struct timeval tpf;
  long ElapsedSec, ElapsedmSec;
  float Elapsed;

  gettimeofday( &tpf, NULL );
/*
  printf("Sec = %ld, microsec = %ld\n", tpf.tv_sec, tpf.tv_usec );
*/
  ElapsedSec = tpf.tv_sec-tpi.tv_sec;
  ElapsedmSec = (tpf.tv_usec-tpi.tv_usec)/1000;
  if ( ElapsedmSec < 0 ) {
     ElapsedSec--;
     ElapsedmSec += 1000;
  }
  Elapsed = (float)ElapsedSec + (float)ElapsedmSec/1000;
/*
  printf("\nElapsed time (watch) = %10.5f\n", Elapsed );
*/
  return(Elapsed);
}