I was to going to write this a long time ago, but never actually been motivated enough. Luckily, the time has finally come.
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Q: What is this?
A: Easy way of finding out which files were modified/added/updated during patching process.
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Q: Why would I need it?
A: If you have a legit version of any given game and want to provide the updated files to those who don't have such version, here's an easy way to find them.
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Q: Is this some arcane knowledge you've just possessed and want to share with us?
A: Nothing arcane about this one. As simple as it gets.
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Q: You realize most of the people here already know this?
A: Of course I do. However, some may not be aware of it, so let's share. Sharing is caring!
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What do I need?
- QuickSFV (Or any other app capable of creating SFV or MD5 files.)
For 32-bit Windows pick 'qsfv236.exe'
For 64- bit Windows pick 'qsfv236x64.exe'
(I personally use QuickSFV, therefore the rest of this guide will be based on it.)
- The original, not-updated, base release. (You must compare something to something after all).
The original fies have to be installed/unpacked and placed inside a separate folder.
- The latest fully updated version.
Which, naturally, should be placed in its own distinct folder.
The basic idea is to compare files using MD5 checksums. So it goes like this:
open folder with the updated version ->> press Ctrl + A ->> right click on any of selected files ->> choose 'Create .SFV File' ->> select MD5 from the drop-down menu (you can insert any name you want; it doesn't matter) ->> hit OK and wait...
copy/paste the newly created md5 file to the root folder of the older, none-updated release ->> double click to run it
Every red entry in the list is either updated or added file.
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Q: Gief some ræl life exapmles pl0x.
A: Sure. I've recently installed FarCry3 - Blood Dragon and then patched it. Let's see which files were actually updated.
I have a backup of the original RELOADED install kept in a separate folder. I also have the latest updated v1.02 version in another one. It's time to compare.
First, go to updated folder. Press Ctrl + A to select all files and folders. Right-click on whichever one you prefer and choose "Create .SFV File".
From the drop-down menu on the right choose .md5 (although .sfv which uses CRC32 should work fine as well) and hit OK.
Drag'n'drop the newly created file into a folder containing the old, outdated version of a game.
Run the file by double clicking on it and wait...
We can now clearly see which files have been updated.
And there we have it! 
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