#include <stdio.h>
#include <stdlib.h>
#include <time.h>

main()
{
  FILE *f;
  time_t t0;

  t0 = time(0);

  srand48(t0 + getpid());

  f = fopen("logfile.txt", "a");
  fprintf(f, "%10d Started: %s", getpid(), ctime(&t0));
  fclose(f);

  sleep(lrand48()%5+1);

  t0 = time(0);

  f = fopen("logfile.txt", "a");
  fprintf(f, "%10d Done:    %s", getpid(), ctime(&t0));
  fclose(f);
 
  exit(0);
}