PRODUCT  :  Borland C++                           NUMBER  :  1706
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  1/2

    TITLE  :  Reading the time and date bitfields for a file.




  Many users need to retrieve the time and date of a file, but
  don't know how to use bitfields. The following example gets the
  time and date using the _dos_getftime() function.

  _dos_getftime() returns the date and time in two unsigned
  integers.  Each unsigned integer is laid out as a bitfield. In
  the example the two structures Time and Date are defined as
  bitfields that match the layout of the values returned by
  _dos_getftime.

  By passing the two structures to _dos_getftime, they will get
  filled in. Then you will be able to retrieve the day, month, and
  other fields as individual structure variables.

  Two things to watch out for are the year and seconds. The year
  is stored as number of years since 1980, so add 1980 to the value
  of the field. The seconds are divided by 2 so multiple by 2 to
  get the correct value. These were done in order to fit all the
  fields into 16 bits.

  The example below opens CONFIG.SYS and gets the time and
  date it was last modified. Make note the bitfields for each
  structure add up to sixteen, the size of an unsigned int. If you
  don't do the same you could have alignment problems, so count
  your bits. The setw() and setfill() in the cout were added for
  the leading zero if minutes is a single digit value. This is
  just for cosmetic reasons. This example should also give you a
  good handle on accessing bitfields in general. Bitfields are a
  valuable tool for saving space.

  #include <iostream.h>
  #include <iomanip.h>
  #include <dos.h>
  #include <fcntl.h>

  void main ()
  {
    struct Time {
      unsigned seconds:5; // Seconds are divded by 2 to save space
      unsigned minutes:6;
      unsigned hours:5;
    } time;














  PRODUCT  :  Borland C++                           NUMBER  :  1706
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  2/2

    TITLE  :  Reading the time and date bitfields for a file.




    struct Date {
      unsigned int day:5;
      unsigned int month:4;
      unsigned int year:7; // The year is store as number of years
    } d8;                  // since 1980

    int hndl;

    if (_dos_open("\\config.sys", O_RDONLY, &hndl))
      cout << "Error open \CONFIG.SYS" << endl;
    else
    {
      if (_dos_getftime(hndl,(unsigned *)&d8, (unsigned *)&time))
         cout << "Error getting CONFIG.SYS's date and time\n";
      else
      {
         cout << "CONFIG.SYS was last modified on: "
                  << d8.month << "/"
                  << d8.day   << "/"
                  << d8.year+1980 << " at "
                  << time.hours << ":" << setw(2) << setfill('0')
                  << time.minutes << ":"
                  << time.seconds * 2 << endl;
      }
      _dos_close(hndl);
    }
  }

  DISCLAIMER: You have the right to use this technical information
  subject to the terms of the No-Nonsense License Statement that
  you received with the Borland product to which this information
  pertains.