Windows doesn’t come with a simple command-line differencing tool as does UNIX/Linux. This is unfortunate because even Windows has to do some scripting from time to time and comparing files manually, correctly, is a pain. Here is a short list of options that I am aware of for differencing files on a Windows system.
The file comparison tool, fc.exe comes with Windows and can perform an ASCII or binary file comparison:
fc file1.txt file2.txt
The windiff.exe tool does the same comparison, but within the Windows GUI. For Windows 2000, 2003 and XP, this tool is in the Support Tools kit, or the Resource Kit for older versions of Windows. The windiff.exe tool can also compare the list of files in folders.
Windows 7 comes with PowerShell, you have to download it for all other versions. Within the powershell are “command-lets” and one of those is compare-object. To compare the contents of two files, you have to use this long, complicated setup:
compare-object -referenceobject $(get-content C:\test\testfile1.txt) -differenceobject $(get-content C:\test\ testfile2.txt)
There is a bundle called “unixutils” that is a Windows 32-bit port of the standard UNIX utilities. I prefer these so much, I actually make a point of installing it on any workstation I use frequently.
diff file1.txt file2.txt
There are also several third party tools, but the one that seems to work best is called WinMerge, which is free and open source.