I have two files and I want to know whether one of them was a copy of the other or not. In other words, how to record the commands used.

[QUOTE=WAMA]how to record the commands used. [/QUOTE]


 
What program?
Doesn't matter, you can't record the commands in Max or Maya.
 
If they look identical, then one is most likely a duplicate of the other. In Studio Max, just turn on Edged faces and take a look at the edge flow. If you give two modelers an assignment to build a model of the exact same object, you will get two models that appear similar, but will look very different when you examine how they were constructed.
 
Another thing you can do is Merge one file into the other. If the merged objects line up perfectly with the existing objects, then one file is a copy of the other. But determining which one is the original and which one is the copy is the hard part.
 
Something else to check would be the file properties. Right click on the files in windows explorer and select Properties from the pop up menu. On the "General" tab of the Properties window you will find a "Created" date and a "Modified" date. This might give you a clue as to when these files were created and worked on. The "Details" tab may also provide more information about who created them.

dear WAMA....................if you wana make this think confirm which was the original file then check which was modified earlier??its simple that copied file must be created later!!!:Pmattresses

Some programs allow the user to create a log of all commands used during a session BUT the feature has to be:1) available...and...2) turned on.A file of this type might have a .log file extension.
John Connor2011-03-13 14:54:03

[QUOTE=kolloer]dear WAMA....................if you wana make this think confirm which was the original file then check which was modified earlier??its simple that copied file must be created later!!!:Pmattresses
[/QUOTE]The copied file will only have been created later if it was edited.  Otherwise, if all the person did was copy it and nothing more then the file size, the date and the time it was created would remain the same. John Connor2011-03-13 15:20:09

[QUOTE=John Connor]The copied file will only have been created later if it was edited.  Otherwise, if all the person did was copy it and nothing more then the file size, the date and the time it was created would remain the same. [/QUOTE]Not necessarily. It's true that the file size would be the same, but the date and time it was created will be different. Take a look at the screenshot below. The file properties on the left are from a file I worked on Friday at work. I stuck it on a flash drive, brought it home and copied it to my desktop. That's why the modified date is March 11 and the Created date is March 12.The file properties on the right are from a copy of that file that I just made. The date and time created are different. I did nothing to the file other than copy and paste in windows explorer. The file was not opened at any time today.

I copy files to my flash drive on a weekly basis and there is no change in the date or time.  Different settings?

I don't know how that can be? If you have a file that you worked on a
year ago, it's creation date is one year ago. So if you make a copy of
that file today, it's creation date should be today because the copy was
created today. I don't see why it's creation date would be one year
ago? As far as you're concerned, it's an exact copy of the original
file, but as far as your computer is concerned, it's a new file that's
just been created.

I've just done some searching but I couldn't find a way to copy a file
and keep the same creation date without using some 3rd party software.

I don't think it matters, but what operating system are you on? I'm on Windows 7 Ultimate.

So you're saying if iIwere to copy all the files off the 3.5" disks I have for AutoCAD for Windows 3.1 and put them on my hard drive the date for each file would change?Win7 64-bit Ultimate too.  Must be our great minds thinking along the same lines!

I think the date would change if I were to do it, but you're saying the creation date does not change when you copy files on your computer. I'm not sure why that is?

Maybe I'm confusing "saving" and "copying".
 
Anyway, with the past couple OS releases when one copies a file doesn't Windows denote the copy in some manner automatically?  I'll have to check.

When I say "Copy" I'm referring to the action of right clicking on a file in windows explorer and then copy and paste. Are you talking about saving out a copy of a file from within the program? 

Test #1.  Copy a dwg file (dated 3/1/2004) into the same directory it resides in.
 
Result: Using Windows XP Pro the file gets preceeded by the words "Copy of xxx.dwg".  The date of the file remains unchanged.  The file size remains the same as well.
 
Test #2.  Copy the same drawing file from my hard drive onto my USB flash drive and into a folder containing the exact same drawing.
 
Result: I first Copy, then try I to Paste.  Up pops a window with the message: "This folder already contains a file named xxx.dwg.  Would you like to replace the existing file with this one?"  There is no way to easily put a duplicate file in the folder on the USB flash drive without overwriting the file that resides there.  One would have to rename the file first.  Example: xxx[rev].dwg.
 
Test #3.  Copy a drawing file (dated 1/19/2001) off my hard drive to my USB flash drive.  Does the file date change in the process?
 
Result: No, it does not.
 
Is there another senario you would like me to test?John Connor2011-03-15 15:37:04

When I copy and paste a file to any location, the creation date is always today's date. If the file already exists, the file name is automatically renamed to "Filename - Copy.xxx". I don't know why it behaves differently on your machine?

I've got such a cool machine that's why.  No, I will not sell it to you.