Last accessed time and last modified time reported by C Run-Time (CRT) functions can be adjusted by using the "Automatically Adjust for Daylight Saving Time" option

MORE INFORMATION

Sample code

   /* STAT.C: This program uses the _stat function to
    * report information about the file named STAT.C.
    * Compile options: none.
    */ 

   #include <time.h>
   #include <sys/types.h>
   #include <sys/stat.h>
   #include <stdio.h>

   int main(int ac, char **av)
   {
      struct _stat buf;

      if(ac != 2)
      {
         printf("Usage: %s <FileName>\n",av[0]);
         return -1;
      }

      /* Get File Statistics for stat.c. */ 
      if( _stat( av[1], &buf ) != 0 )
         perror( "Problem getting information" );
      else /* print the date/time last modified */ 
         printf( "Date/Time modified : %s", ctime( &buf.st_mtime ) );
   }
   /* End stat.c. */ 
				

Steps to reproduce the behavior (must be an NTFS drive)

1. Open the Date/Time Properties dialog box and ensure that "Automatically Adjust For Daylight Saving Time" is selected. Press OK.
2. Set your system date to a date that is during daylight saving time (for example, 10/25/97 in the "Pacific Time (US & Canada); Tijuana" time zone).
3. Create a new file called repro.txt.
4. Note the date/time last modified for repro.txt, as reported by either the Windows Explorer or using an MS-DOS dir command.
5. At the MS-DOS prompt, run "c:\>stat.exe repro.txt", and note that the date/time last modified matches the date/time last modified that the system reports.
6. Reset your system date to a date that is in the standard time period.
7. Look again at an MS-DOS dir command (or in the Windows Explorer) and you can see that the time last modified for repro.txt is now one hour earlier than before.
8. Repeat step 5, and note that the date/time reported by stat.exe is also one hour earlier, matching what the operating system reports.
9. Clear "Automatically Adjust for Daylight Saving Time."
10. Repeat steps 7 and 8, noting that the adjustment is not being made, and the time last modified has returned to its original value.