how to try to open a database without creating one?

[davepacheco]

I want to write a debugging tool that dumps the contents of my program's sled database (while the program is not running). I know there's Db::was_recovered() to determine if the database already existed before it was opened. But what if I want to not open it if it doesn't already exist? I tried passing create_new(false) but that appeared to have no effect.