Git: “please tell me who you are” error

I spent lots of hours on it when I call PHP script to init and commit to git.
And I found the work flow should be as:

1. git init
2. git config user.name "someone"
3. git config user.email "someone@someplace.com"
4. git add *
5. git commit -m "some init msg"

If you swap [23] and 1, the config will not work at all.

I wish this will do some help.