git commit -a confusion

Question

I am using Git Bash and am trying to figure out what is happening when I type \'git commit -a\'.

Looks like VIM opens up to edit my commit message but how do I save

Answer 1

Just leave VIM (command mode -> :wq).

-a flag works like:

git add -u
git commit ...

-m flag specifies commit message. That message is mandatory so if you don't pass that (git commit -m "My message") the default text editor will be opened (you can change it in git configuration) and you'll have to write a commit message, then save and quit the editor.