There are times notifications aren't wanted about either a changed repo file or a new file that needs to be added to the repo.  However, adding the name of the file to `.gitignore` might not be a good option, either.  For example, locally-generated files that other users aren't likely to generate (e.g., files created by an editor) or files of experimental test code might not be appropriate to appear in a `.gitignore` file.

In those cases, use one of these solutions:

 0. **If the file is a changed repo file**

    Use the command:

    `git update-index --assume-unchanged "$FILE"`

    To undo this, use the command:

    `git update-index --no-assume-unchanged "$FILE"`

    The `update-index` command doesn't work with new files that haven't been added to the repo yet, though.

 0. **If the file is new and not added to the repo**

    Add its filename to the repo's `exclude` file:

    `echo "$FILE" >> .git/info/exclude`

    This also works for changed repo files, but there isn't a specific undo command for it.  The `exclude` file would need to be edited and the filename deleted from it.  Or other commands could approximate it:

    `ex -s -c"g/^${FILE}\$/d" -cwq .git/info/exclude`

    Note that this overwrites the existing `exclude` file and if the filename specified contains special characters that could affect the regular expression, the results are unpredictable.

    This usage of the `exclude` file is recommended by the page ["Ignoring files" on GitHub Help](https://help.github.com/articles/ignoring-files/#explicit-repository-excludes).