file attributes - Windows equivalent of the Linux command 'touch'?

What do you use when you want to update the date-modified field of a file on Windows?

1. commands accessible via C++, .NET, C#, or something native to Windows (Vista preferably)


2. tools/applications preferably free, and if possible open source as well

Edit: there is already a page for applications as pointed out by CheapScotsman here.

If anyone knows how I can do this via C++, C#, WSH or something similar, well and good, else I would think everything else is covered in the linked question.

Answer

If you want to touch the date stamp of a file using windows, use the following command at the command prompt:

copy /b filename.ext +,,

(where filename.ext is your file's name). The +,, is a special flag to copy telling it to simply update the date/time on the file:

* Changing the time and date of a file

If you want to assign the current time and date to a file without modifying the file, use the following syntax:

copy /b Source+,,

The commas indicate the omission of the Destination parameter.

Edit based on comments by Lumi and Justin: put this in a batch file, eg. touch.cmd

@COPY /B %1+,, %1

This works even if the file is not in the current directory (tested on Windows 7).