how to configure an existing git repo to be shared with unix group

gistfile1.txt

#by David UnderHill @ http://stackoverflow.com/questions/3242282/how-to-configure-an-existing-git-repo-to-be-shared-by-a-unix-group

ex: share a git repo to a group called foo

chgrp -R foo repodir                # set the group
chmod -R g+rw repodir               # allow the group to read/write
chmod g+s `find repodir -type d`    # new files get group id of directory

config.sharedRepository = true