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 <file>, the paths before it will move to the end and output.

`--skip-to=`<file>

  Start showing the diff for <file>, 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`.

`--symlinks`
`--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`
`--gui`
`--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.

`--trust-exit-code`
`--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