Is there a function that opens a file chooser minibuffer and returns an absolute file name?

Question

I want to write a function in my init.el file that basically opens a file-browser minibuffer for the user (the standard one or the one from helm) and returns an absolute file name to be used in another function.

Answer 1

You're describing read-file-name (which will use different UIs depending on the user's configuration and/or whether he triggered the current command with the mouse or with the keyboard).