Run git commands without default gitconfig

Question

Is there a way to run git commands without using the default gitconfig?

For example, say I had setup a custom diff tool in my gitconfig. If I wanted to use the default git diff (which uses diff?), how would I do it?

Thanks!

Answer 1

Use the --ext-diff option with git diff. --ext-diff allows you to specify a different external diff tool.

Answer 2

To ignore the system Git config (/etc/gitconfig), set the environment variable GIT_CONFIG_NOSYSTEM to 1 (or true or yes). To ignore the global Git config (~/.gitconfig), set the environment variable GIT_CONFIG_NOGLOBAL to 1 (or true or yes).

Example: GIT_CONFIG_NOGLOBAL=1 git diff

These options are available since ab88c36 (allow suppressing of global and system config, 2008-02-06). The first release (candidate) that appears to know them is 1.5.5-rc0 (git describe --contains ab88c36).

Answer 3

Use GIT_CONFIG_NOGLOBAL=1 HOME= XDG_CONFIG_HOME= git diff to ensure that no outside configuration at all is read by git.

From the official documentation:

GIT_CONFIG_NOSYSTEM

Whether to skip reading settings from the system-wide $(prefix)/etc/gitconfig file. This environment variable can be used along with $HOME and $XDG_CONFIG_HOME to create a predictable environment for a picky script, or you can set it temporarily to avoid using a buggy /etc/gitconfig file while waiting for someone with sufficient permissions to fix it.