SHELL

git username

$ git config --global user.name
> "John Smith"

$ git config --global user.email 
> "johnsmith@example.com"

if you have configured multiple git users in your machine
$ git config --global user.name ### It will give name of git user who is globaly scoped
$ git config user.name ### It will give name of git user who has scope with respect to current repository

git username

The command git config --list will list the settings. There you should also find user.name and user.email.