How does Vim's autoread work?

Question

:h autoread says:

When a file has been detected to have been changed outside of Vim and it has not been changed inside of Vim, automatically

Answer 1

As per my posting on superuser.com

Autoread just doesn't work. Use the following.

http://vim.wikia.com/wiki/Have_Vim_check_automatically_if_the_file_has_changed_externally

I got the best results by calling the setup function directly, like so.

let autoreadargs={'autoread':1} 
execute WatchForChanges("*",autoreadargs) 

The reason for this, is that I want to run a ipython/screen/vim setup.