If you haven't committed the files yet, i'd say add the filename to your .gitignore
file like:
<filename>.<extension>
So in case the file is package.json:
package.json
Wildcards can be made by using the *
*.json
or as AoeAoe remarked: you can add the file later using git add --force
to overrule the .gitignore
file.
Now if the content of your file is merely 10 rules of config, i'd say: create a mock-up out of it and write it down in your readme.md
and instruct your colleagues to create their own, otherwise, you should follow the advice in the update section.
Update: as Edward Thompson stated: .gitignore doesn't apply to uploaded files you'll be forced to use git update-index
To force the file from not updating:
git update-index --assume-unchanged path/to/file
To enable updating again:
git update-index --no-assume-unchanged path/to/file