Solved

File.SetLastWriteTime Not working as planned

Posted on 2014-01-28
9
527 Views
Last Modified: 2014-02-21
Hi All,
I am trying to set the File.SetLastWriteTime with that of a file that it was copied from.
It kinda works.  Problem is that when getting the new GetLastWriteTime it is one or two seconds greater than the date/time provided.

For instance if the Source file is 01/28/2014 1:18 PM, the Destination file, that is being altered, shows a value of 01/28/2014 1:20 PM. It's as if the SetLastWriteTime is working but taking a couple seconds, so that a new value is set.

example: (TDest$ and TSource$ are files, including paths)
File.SetLastWriteTime(TDest$, File.GetLastWriteTime(TSource$))

Any ideas?
0
Comment
Question by:Thunder724
  • 4
  • 3
  • 2
9 Comments
 
LVL 83

Expert Comment

by:CodeCruiser
ID: 39816487
That is actually 2 minutes not seconds. Is there any other code between the setting the time and closing the file?
0
 
LVL 4

Author Comment

by:Thunder724
ID: 39816535
Oh, sorry.... My fault in the example. it is actually seconds not minutes; I forgot to add the minute part.  No there is nothing between the code at all, that's why its driving me insane.
0
 
LVL 83

Expert Comment

by:CodeCruiser
ID: 39816542
Can you show your code?
0
Master Your Team's Linux and Cloud Stack

Come see why top tech companies like Mailchimp and Media Temple use Linux Academy to build their employee training programs.

 
LVL 4

Author Comment

by:Thunder724
ID: 39816551
sure, I put it in the original message.
But before that I am copying these files first.  
I even tried changing the SetLastWriteTime after the function that runs and contains the CopyFile function.

My.Computer.FileSystem.CopyFile(TSource$, TDest$, FileIO.UIOption.AllDialogs, FileIO.UICancelOption.ThrowException)

File.SetLastWriteTime(TDest$, File.GetLastWriteTime(TSource$))
0
 
LVL 83

Expert Comment

by:CodeCruiser
ID: 39817332
If you do a

msgbox File.GetLastWriteTime(TSource$)

do you get the same datatime stamp as you see in explorer?
0
 
LVL 4

Author Comment

by:Thunder724
ID: 39818185
I can't explain it; but it looks to be working correctly now. I really didn't do anything either.
I will get back to you tomorrow to close this if everything is still testing out correctly.  
Thanks very much for you help.
0
 
LVL 28

Expert Comment

by:Ark
ID: 39820141
Which file system was on TDest$?
According to http://www.xxcopy.com/xxcopy15.htm
For the compatibility's sake, even WinNT/2K
  uses the same 2-second granularity for the "Last-modified" time for
  FAT-based file system (does not apply for NTFS files).
0
 
LVL 4

Author Comment

by:Thunder724
ID: 39825273
NTFS.
it seems to be a specific issue only when syncing to/from a usb stick.
0
 
LVL 28

Accepted Solution

by:
Ark earned 500 total points
ID: 39825782
There is another issue with NTFS - it does store time stamps with 100 ns granularity but it UPDATES values only after 1 hour
0

Featured Post

Master Your Team's Linux and Cloud Stack

Come see why top tech companies like Mailchimp and Media Temple use Linux Academy to build their employee training programs.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This document covers how to connect to SQL Server and browse its contents.  It is meant for those new to Visual Studio and/or working with Microsoft SQL Server.  It is not a guide to building SQL Server database connections in your code.  This is mo…
More often than not, we developers are confronted with a need: a need to make some kind of magic happen via code. Whether it is for a client, for the boss, or for our own personal projects, the need must be satisfied. Most of the time, the Framework…
Email security requires an ever evolving service that stays up to date with counter-evolving threats. The Email Laundry perform Research and Development to ensure their email security service evolves faster than cyber criminals. We apply our Threat…

840 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question