Frequently Asked Questions about WinMerge

WinMerge says "Binary files are different", but I am not comparing binary files?

Your files may use an unsupported character set, such as UCS-2 or UTF-16, which are two Unicode character sets popular on MS-Windows. WinMerge only interprets Unicode text files as text if they use the UTF-8 (or UTF-7) character sets. Full unicode support is planned for the next version of WinMerge. Check http://winmerge.sourceforge.net for updates.

WinMerge cannot compare registry files (*.reg)?

Windows registry files (*.reg) are UTF-16 or UCS-2 (does anyone know which ?) -- see previous answer.

I cannot merge binary files?

WinMerge can only show if binary files are identical or different.

Differences don't line up in the display?

Try disabling Edit->Options...->Ignore Blank Lines, that should make it line up again.

That splash screen is annoying, how do I turn it off?

Go to Edit->Options...->Disable Splash Screen

Some characters are cut in half?

Try selecting a different font on View->Select Font...

What is RegExp? How do I define my own regexps?

RegExp is regular expression. There is a lots of documentation on the net, you can for example look at:
  http://www.amk.ca/python/howto/regex/ (Regular Expression HOWTO)
  http://www.zvon.org/other/PerlTutorial/Output/index.html (Tutorial)
  http://gmckinney.info/resources/regex.pdf (Quick reference)

Can I export/import a patch file? Is there a way to copy difference(s) to clipdoard?

WinMerge writes diff.txt file to your $temp path. Exporting/importing patch files is planned for the next version of WinMerge. Check http://winmerge.sourceforge.net for updates.

Why is the option "Ignore blank lines" always disabled?

Because it does not work properly in the current code, so it was decided it was better to disable the option. If somebody (maybe you) fixes it, then it will be enabled in the next version of WinMerge.

I would like to see the line numbers?

WinMerge does not currently show line numbers. It is planned for the next version of WinMerge. Check http://winmerge.sourceforge.net for updates.

When wanting to compare directories, I cannot select a directory in Browse?

Are you trying to select a directory by clicking on it in the upper part of the Open File dialog ? The OpenFile dialog will then open it, and you have to push Ok again to get out.

I am using WinMerge as a backend to TortoiseCVS, and the temporary file names are being added to my MRU list, which wrecks the MRU list.

Tell TortoiseCVS to invoke WinMerge with the /ub option, which tells WinMerge to not add the files to the MRU.

I am using WinMerge as a backend to WinCVS, and the temporary file names are being added to my MRU list, which wrecks the MRU list.

You need to tell WinCVS to invoke WinMerge with the /ub option, which tells WinMerge to not add the files to the MRU. Unfortunately WinCVS 1.2 and 1.3 does not work with switches (bug in WinCVS 1.2 and 1.3?). You cannot add switches to Admin/Preferences/WinCVS. Instead you can create a batch file where you add one of these lines (but not both):

  CALL "<winmerge path>\WinMerge" /ub %1 %2
  start "WinMerge" "<winmerge path>" /ub %1 %2

Where <winmerge path> is the path to where you have WinMerge installed, then tell WinCVS to call this batch file.

I want to fix a bug or implement a new feature in WinMerge, how do I do that?

Get sources from CVS ( The cvs page of the project has a (terse) description of how to get the sources.) and submit your changes as a patch. Easiest way is to zip changed files and upload that zip file.

My question is not on the list, what do I do?

Read the documentation again, and try to figure it out yourself. If you still can't figure it out, then look at the winmerge-user mailinglist if your question might have already been asked by somebody else. If it is not on the winmerge-user mailinglist, then you can ask it there yourself.