Opening files and folders

You can use environment variables in your paths. Windows expands the variable name between % (percent) delimiters. For example, if an environment variable named WORKDIR has the value c:\workfiles, then the path %WORKDIR%\project1 is expanded to c:\workfiles\project1 .

WinMerge archive support is provided in the 7-Zip plugin. See Getting and installing WinMerge to install this plugin.

Opening two archive files is similar to opening normal files: specify two archive files in the Open-dialog's Left and Right fields. If WinMerge recognizes the archive format, it opens the contents of the archive files in the Folder Compare window.

The Comparing and merging folders topic describes how to work with archive files. For example, if an archive file contains two subfolders named Original/ and Altered/, you can compare the contents of the two subfolders by specifying the same archive file in both sides in the Select Files or Folders dialog or WinMerge command line.

	Tip
	When you drag an archive file to the WinMerge window, press Shift when dropping the file: WinMerge automatically copies the same filename to both sides and opens the archive file.

The Filter edit field enables you to restrict the files to be included in your folder compare. You can specify one or more file masks, or a single file filter (not both).

A mask is a simple expression based on file extensions. For example, this list of file masks includes only files with the specified extensions; all others are excluded from the selection when the compare operation starts:

*.h;*.cpp *.txt,*.ini

File masks are practical for simple filtering; for more advanced selecting, use filter files. Filter files are collections of regular expressions that can either include or exclude files. WinMerge installs a number of predefined filter files in its Filters folder, and you can create your own, too.

To specify a filter, click the Select button next to the Filters field to choose from a list of available filters. Or, click the Filter drop-down list and choose a recently-used filter file.

For full information about filter masks and filter files, see Using Filters.

Unpackers are plugins that are installed with WinMerge to provide functionality that is not used by default. Plugins that can be used to preprocess certain types of files before comparing them. For example, WinMerge cannot normally compare MS Word doc files, but by unpacking them, you can compare just the text contents. See Plugins for details.

To apply a plugin to your file comparison, click the Select button for the Unpacker option. In the Select Unpacker dialog:

Your choice is displayed in the Unpacker field. Note that you cannot select an unpacker when launching a Folder Compare operation.

The Windows Explorer shell integration is available only if enabled. You can enable it either during WinMerge installation or later, using the Shell Integration page in the Options window. In the Options window, configure the Add to context menu option, including its suboptions if you like.

If you enable Add to context menu without the advanced menu suboption, the WinMerge shortcut is added to the Explorer context menu. For example:

To use the basic shell integration, begin by selecting two paths in Windows Explorer. Then, right-click and choose WinMerge in the context menu. For example:

WinMerge opens the paths directly in the File Compare or Folder Compare window.

The left and right sides are determined by the sort order in Windows Explorer. In the preceding screen shot, the Windows Explorer file list is in ascending order, so WinMerge opens with File2 on the left side and File1 on the right..

	Note
	If either path cannot be opened for any reason, WinMerge opens the Select Files or Folders dialog, where you can specify new paths. Similarly, if you select only a single path, the Select Files or Folders dialog opens with the selected file or folder in the Left field, leaving the Right path for you to specify.

The WinMerge shortcut is quick and easy to use, but you can compare only files or folders that you are able to select concurrently in Windows Explorer. For more flexible selections, consider enabling the advanced menu, described in the next section.

If you choose the Enable advanced menu, the WinMerge shortcut is replaced with two Compare shortcuts:

Use the Compare shortcuts in this order:

	Note
	If you click Compare before designating the first path, the Select Files or Folders dialog is opened, with your selection as the first (Left) path. Specify the second path in the Right field to continue with the comparison.

The Compare To paths is stored in memory until WinMerge is opened. As a result, you don't need to select both files at the same time or even using the same Windows Explorer view: you can choose one, open a different directory, and choose the other one. Both paths are discarded from memory after a compare operation. This means that you cannot select one Compare To path and compare it against several paths.

By default, folder compares that you do using the WinMerge or Compare shortcut are not recursive: only files in the top level are included. There are two ways to launch recursive compares with the Windows Explorer integration:

	Note
	These settings for the Windows Explorer integration do not change the Include Subfolders setting for the Select Files or Folders dialog, described in Quick start.

To use a project file In the WinMerge window, click File → Open Project. WinMerge reads the paths from the project file. If the project file has two paths, both paths are opened. If only one path is given or one of paths is invalid, WinMerge opens the Select Files or Folders dialog, where you can add or correct the path information. Here are a few things to consider:

To specify a project file on the command line, simply enter it as a single file path.

To save a project file, click File → Save Project. The Project File dialog provides fields and options that you can easily edit to build a project file. If a compare window is currently open, the Project File dialog is initialized with values from the current compare; otherwise, you provide the values yourself. To use an existing project, click Open and select a project to load its values (any existing values are overwritten in the dialog).

When you finished editing, click Save to store the file.

Project files are simple XML files with a .WinMerge extension. For example:

<?xml version='1.0' encoding='UTF-8'?>
<project>
   <paths>
      <left>c:\work\project1</left>
      <left-readonly>1</left-readonly>
      <right>c:\work\project2</right>
      <right-readonly>0</right-readonly>
      <filter>Visual C++ loose</filter>
      <subfolders>0</subfolders>
   </paths>
</project>

A project file contains a paths element that can contain one of each of these elements:

None of the fields is required, and they can be empty (for example, <left></left> or <left/>).