ceph/src/boost/libs/date_time/xmldoc/ex_print_hours.xml

   1 <?xml version="1.0" encoding="utf-8"?>
   2 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   3 "../../../tools/boostbook/dtd/boostbook.dtd">
   4
   5 <!-- Copyright (c) 2001-2004 CrystalClear Software, Inc.
   6      Subject to the Boost Software License, Version 1.0.
   7      (See accompanying file LICENSE_1_0.txt or  http://www.boost.org/LICENSE_1_0.txt)
   8 -->
   9
  10 <section id="date_time.examples.print_hours">
  11   <title>Print Hours</title>
  12
  13   <para>
  14     Demonstrate time iteration, clock retrieval, and simple calculation.
  15   </para>
  16   <programlisting>
  17     <![CDATA[
  18   /* Print the remaining hours of the day
  19    * Uses the clock to get the local time
  20    * Use an iterator to iterate over the remaining hours
  21    * Retrieve the date part from a time
  22    *
  23    * Expected Output something like:
  24    *
  25    * 2002-Mar-08 16:30:59
  26    * 2002-Mar-08 17:30:59
  27    * 2002-Mar-08 18:30:59
  28    * 2002-Mar-08 19:30:59
  29    * 2002-Mar-08 20:30:59
  30    * 2002-Mar-08 21:30:59
  31    * 2002-Mar-08 22:30:59
  32    * 2002-Mar-08 23:30:59
  33    * Time left till midnight: 07:29:01
  34    */
  35
  36   #include "boost/date_time/posix_time/posix_time.hpp"
  37   #include <iostream>
  38
  39   int
  40   main()
  41   {
  42     using namespace boost::posix_time;
  43     using namespace boost::gregorian;
  44
  45     //get the current time from the clock -- one second resolution
  46     ptime now = second_clock::local_time();
  47     //Get the date part out of the time
  48     date today = now.date();
  49     date tommorrow = today + days(1);
  50     ptime tommorrow_start(tommorrow); //midnight
  51
  52     //iterator adds by one hour
  53     time_iterator titr(now,hours(1));
  54     for (; titr < tommorrow_start; ++titr) {
  55       std::cout << to_simple_string(*titr) << std::endl;
  56     }
  57
  58     time_duration remaining = tommorrow_start - now;
  59     std::cout << "Time left till midnight: "
  60               << to_simple_string(remaining) << std::endl;
  61     return 0;
  62   }
  63
  64     ]]>
  65   </programlisting>
  66 </section>