/*********************************************************
 * From C PROGRAMMING: A MODERN APPROACH, Second Edition *
 * By K. N. King                                         *
 * Copyright (c) 2008, 1996 W. W. Norton & Company, Inc. *
 * All rights reserved.                                  *
 * This program may be freely distributed for class use, *
 * provided that this copyright notice is retained.      *
 *********************************************************/

/* datetime.c (Chapter 26, page 700) */
/* Displays the current date and time in three formats */

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

int main(void)
{
  time_t current = time(NULL);
  struct tm *ptr;
  char date_time[21];
  int hour;
  char am_or_pm;

  /* Print date and time in default format */
  puts(ctime(&current));

  /* Print date and time, using strftime to format */
  strftime(date_time, sizeof(date_time),
           "%m-%d-%Y  %I:%M%p\n", localtime(&current));
  puts(date_time);

  /* Print date and time, using printf to format */
  ptr = localtime(&current);
  hour = ptr->tm_hour;
  if (hour <= 11)
    am_or_pm = 'a';
  else {
    hour -= 12;
    am_or_pm = 'p';
  }
  if (hour == 0)
    hour = 12;
  printf("%.2d-%.2d-%d  %2d:%.2d%c\n", ptr->tm_mon + 1,
         ptr->tm_mday, ptr->tm_year + 1900, hour,
         ptr->tm_min, am_or_pm);

  return 0;
}