git-difftool(1)

# git-difftool(1) Manual Page

## NAME

git-difftool - Show changes using common diff tools

## SYNOPSIS

    git difftool [<options>] [<commit> [<commit>]] [--] [<path>…​]

## DESCRIPTION

git difftool is a Git command that allows you to compare and edit files between revisions using common diff tools. git difftool is a frontend to git diff and accepts the same options and arguments. See git-diff(1).

## OPTIONS

-d
--dir-diff

  Copy the modified files to a temporary location and perform a directory diff on them. This mode never prompts before launching the diff tool.

-y
--no-prompt

  Do not prompt before launching a diff tool.

--prompt

  Prompt before each invocation of the diff tool. This is the default behaviour; the option is provided to override any configuration settings.

--rotate-to=<file>

  Start showing the diff for the given path, the paths before it will move to the end and output.

--skip-to=<file>

  Start showing the diff for the given path, skipping all the paths before it.

-t <tool>
--tool=<tool>

  Use the diff tool specified by <tool>. Valid values include emerge, kompare, meld, and vimdiff. Run `git` `difftool` `--tool-help` for the list of valid <tool> settings.

  If a diff tool is not specified, git difftool will use the configuration variable `diff.tool`. If the configuration variable `diff.tool` is not set, git difftool will pick a suitable default.

  You can explicitly provide a full path to the tool by setting the configuration variable `difftool.`<tool>`.path`. For example, you can configure the absolute path to kdiff3 by setting `difftool.kdiff3.path`. Otherwise, git difftool assumes the tool is available in PATH.

  Instead of running one of the known diff tools, git difftool can be customized to run an alternative program by specifying the command line to invoke in a configuration variable `difftool.`<tool>`.cmd`.

  When git difftool is invoked with this tool (either through the `-t` or `--tool` option or the `diff.tool` configuration variable) the configured command line will be invoked with the following variables available: `$LOCAL` is set to the name of the temporary file containing the contents of the diff pre-image and `$REMOTE` is set to the name of the temporary file containing the contents of the diff post-image. `$MERGED` is the name of the file which is being compared. `$BASE` is provided for compatibility with custom merge tool commands and has the same value as `$MERGED`.

--tool-help

  Print a list of diff tools that may be used with `--tool`.

--[no-]symlinks

  git difftool's default behavior is to create symlinks to the working tree when run in `--dir-diff` mode and the right-hand side of the comparison yields the same content as the file in the working tree.

  Specifying `--no-symlinks` instructs git difftool to create copies instead. `--no-symlinks` is the default on Windows.

-x <command>
--extcmd=<command>

  Specify a custom command for viewing diffs. git-difftool ignores the configured defaults and runs <command> `$LOCAL` `$REMOTE` when this option is specified. Additionally, `$BASE` is set in the environment.

-g
--[no-]gui

  When git-difftool is invoked with the `-g` or `--gui` option the default diff tool will be read from the configured `diff.guitool` variable instead of `diff.tool`. This may be selected automatically using the configuration variable `difftool.guiDefault`. The `--no-gui` option can be used to override these settings. If `diff.guitool` is not set, we will fallback in the order of `merge.guitool`, `diff.tool`, `merge.tool` until a tool is found.

--[no-]trust-exit-code

  Errors reported by the diff tool are ignored by default. Use `--trust-exit-code` to make git-difftool exit when an invoked diff tool returns a non-zero exit code.

  git-difftool will forward the exit code of the invoked tool when `--trust-exit-code` is used.

See git-diff(1) for the full list of supported options.

## CONFIGURATION

git difftool falls back to git mergetool config variables when the difftool equivalents have not been defined.

Everything above this line in this section isn’t included from the git-config(1) documentation. The content that follows is the same as what’s found there:

diff.tool

  Controls which diff tool is used by git-difftool(1). This variable overrides the value configured in `merge.tool`. The list below shows the valid built-in values. Any other value is treated as a custom diff tool and requires that a corresponding difftool.<tool>.cmd variable is defined.

diff.guitool

  Controls which diff tool is used by git-difftool(1) when the -g/--gui flag is specified. This variable overrides the value configured in `merge.guitool`. The list below shows the valid built-in values. Any other value is treated as a custom diff tool and requires that a corresponding difftool.<guitool>.cmd variable is defined.

  `araxis`

    Use Araxis Merge (requires a graphical session)

  `bc`

    Use Beyond Compare (requires a graphical session)

  `bc3`

    Use Beyond Compare (requires a graphical session)

  `bc4`

    Use Beyond Compare (requires a graphical session)

  `codecompare`

    Use Code Compare (requires a graphical session)

  `deltawalker`

    Use DeltaWalker (requires a graphical session)

  `diffmerge`

    Use DiffMerge (requires a graphical session)

  `diffuse`

    Use Diffuse (requires a graphical session)

  `ecmerge`

    Use ECMerge (requires a graphical session)

  `emerge`

    Use Emacs' Emerge

  `examdiff`

    Use ExamDiff Pro (requires a graphical session)

  `guiffy`

    Use Guiffy’s Diff Tool (requires a graphical session)

  `gvimdiff`

    Use gVim (requires a graphical session)

  `kdiff3`

    Use KDiff3 (requires a graphical session)

  `kompare`

    Use Kompare (requires a graphical session)

  `meld`

    Use Meld (requires a graphical session)

  `nvimdiff`

    Use Neovim

  `opendiff`

    Use FileMerge (requires a graphical session)

  `p4merge`

    Use HelixCore P4Merge (requires a graphical session)

  `smerge`

    Use Sublime Merge (requires a graphical session)

  `tkdiff`

    Use TkDiff (requires a graphical session)

  `vimdiff`

    Use Vim

  `vscode`

    Use Visual Studio Code (requires a graphical session)

  `winmerge`

    Use WinMerge (requires a graphical session)

  `xxdiff`

    Use xxdiff (requires a graphical session)

difftool.<tool>.cmd

  Specify the command to invoke the specified diff tool. The specified command is evaluated in shell with the following variables available: LOCAL is set to the name of the temporary file containing the contents of the diff pre-image and REMOTE is set to the name of the temporary file containing the contents of the diff post-image.

  See the `--tool=`<tool> option in git-difftool(1) for more details.

difftool.<tool>.path

  Override the path for the given tool. This is useful in case your tool is not in the PATH.

difftool.trustExitCode

  Exit difftool if the invoked diff tool returns a non-zero exit status.

  See the `--trust-exit-code` option in git-difftool(1) for more details.

difftool.prompt

  Prompt before each invocation of the diff tool.

difftool.guiDefault

  Set `true` to use the `diff.guitool` by default (equivalent to specifying the `--gui` argument), or `auto` to select `diff.guitool` or `diff.tool` depending on the presence of a `DISPLAY` environment variable value. The default is `false`, where the `--gui` argument must be provided explicitly for the `diff.guitool` to be used.

## SEE ALSO

git-diff(1)

  Show changes between commits, commit and working tree, etc

git-mergetool(1)

  Run merge conflict resolution tools to resolve merge conflicts

git-config(1)

  Get and set repository or global options

## GIT

Part of the git(1) suite