How to change file modification date in Windows

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: How to change file modification date in Windows by Ido (Hermit) on Nov 12, 2002 at 17:22 UTC
In order to change the modification date of a file you should use the utime function (`utime ACCESSTIME,MODIFICATIONTIME,LIST` - Times in numerical format, and list is a list of files). Read more about it in perlfunc -f utime.	[reply] [d/l]
Re: How to change file modification date in Windows by John M. Dlugosz (Monsignor) on Nov 12, 2002 at 17:22 UTC
Wow, I figured as a late replier the question would have been answered already. The Win32 API function is `SetFileTimes`. Use the Win32::API module to call it. Treat the 3 timestamp parameters as 8-byte buffers and don't worry about how to manipulate them, since you'll just save the results from `GetFileTimes`. —John	[reply] [d/l] [select]
(z) Re: How to change file modification date in Windows by zigdon (Deacon) on Nov 12, 2002 at 16:11 UTC
Why not just use the stat command? `my $filename = "Test.txt"; print "$filename was last modified on: ", scalar localtime((stat($file +name))[9]), "\n";` [download] -- Dan	[reply] [d/l]
Re: How to change file modification date in Windows by Thelonius (Priest) on Nov 12, 2002 at 17:16 UTC
I'm not aware of any Windows command that does it, but if you load cygwin on your machine, you can do it with the `touch` command.	[reply] [d/l]
Re: Re: How to change file modification date in Windows by Rex(Wrecks) (Curate) on Nov 12, 2002 at 19:00 UTC
Actually Borlands free compiler tools contain the touch command for win32. I think some of the MKS style tools kits do it as well. Unless you really need a different shell, you can find most GNU/Unix commands ported to the win32 cmd.exe shell without the overhead and hassle of cygwin. "Nothing is sure but death and taxes" I say combine the two and its death to all taxes!	[reply]
Re: How to change file modification date in Windows by Anonymous Monk on Nov 12, 2002 at 18:49 UTC
Thank you all! I can use the `stat`function to grab the time before I modify the file, and then pass that to `utime` to restore it after my changes. Just what I wanted to do! Thanks again! - dp	[reply] [d/l] [select]
Re: How to change file modification date in Windows by robartes (Priest) on Nov 12, 2002 at 16:16 UTC
If you want to read the modification date after your mods, see zigdon's answer. If you want to change the date back to what it was: why do you want to cover your tracks? CU Robartes-	[reply]
Re: Re: How to change file modification date in Windows by Anonymous Monk on Nov 12, 2002 at 16:26 UTC
These are data files that I recieve from analysts and the mod date gives me a quick read on when they did the analysis. Usually I get updated data files with the same names so my only "version control" is by the date. - dp	[reply]
Re: Re: Re: How to change file modification date in Windows by robartes (Priest) on Nov 12, 2002 at 18:05 UTC
In that case, use zigdon's suggestion: stat. Sorry I misunderstood your question. CU Robartes-	[reply]