Thursday, March 24, 2005

Time really is relative and Bill Gates knows this.

This morning Bruce was working on some stuff on our PVCS server here at work. While running a file compare on several files he checked out of PVCS he noticed that the Modified Time on those files he checked out onto the Windows XP were different from the exact same files checked out onto the Novell Network. The time difference was exactly one hour.

What we determined is that Windows will adjust the time in accordance to it's own time settings. If you change your time zone, your file modified timestamps will change. Therefore in Windows, Time is Relative. So can you even trust Date Related File Attributes? I don't think so.

I did a little experiement. I took a text file that's on my hard drive, and did the following. for sake of argument the file will be called index.html (modified Date: 05/14/2004 11:42am)

  1. Changed Local windows setting from CST to CDT by advancing the month to April.
    - File Time advanced 1 hour to 12:43pm
  2. Moved index.html to the LAN where windows can't control the date paramenters.
  3. Changed Local Windows time back to CST by setting month back to March
  4. Moved index.html back to my hard drive.
    - File Time stayed at 12:43pm
  5. Changed Local windows setting from CST to CDT by advancing the month to April.
    - File Time advanced 1 hour to 1:43pm
  6. Moved index.html to the LAN where windows can't control the date paramenters.
  7. Changed Local Windows time back to CST by setting month back to March
  8. Moved index.html back to my hard drive.
    - File Time stayed at 1:43pm
  9. Changed local time to (GMT+2:00 Cairo)
    - File Date/ Time ajusted to 05/19/2004 6:43AM
  10. Moved index.html to the LAN where windows can't control the date paramenters.
  11. Changed Local Windows time back to cst and Central Time
  12. Moved index.html back to my hard drive.
    - File Date/ Time stayed at 05/19/2004 6:43AM

I understand why this happens. If time's relative and I save this blog at 12:05PM it's really 1:05PM in Toronto. Also a File I changed in June of 2004 may have been changed at 11:30am but the fact that it's now Standard time I really did this at 10:30am in relation to the current time structure. To prevent people from doing needless math, Microsoft decides to "Fix" this for you. This can cause problems too.

In the past there have been many incidents regarding Daylight Savings Time changes. My issue isn't that Microsoft does this, (I haven't decided for sure yet.) my real issue is that Billy boy must think that EVERY computer out there is running Windows® and that all systems will accommodate this. This is either very optimistic, arrogant or merely an oversight. However, the excuse of, "Sorry Prof. My essay is late because my printer broke and my Internet was down, but the file date proves I was done on time." doesn't hold water anymore.

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