title: How to get return (status) value of an external command in Vim
body: <p>I want to get the exit value (returned by <code>$?</code> on a shell; usually 0 or 1 for success or failure) of a external shell command in Vim. Note that I want to get its standard output too. So I can use the output and the also the exit value in a Vim conditional expression. Is this possible?</p>