title: Wordpress: Add a <link> tag to <head>
body: <p>I have a button in my plugin that creates a file based on user input. Now, I want to include that file in every page (frontend). I could simply inject a script, but the problem is that one website may recreate the file multiple times, which would result in having several instances of  in website head, which I'd like to avoid. Is there a way to programatically do this within wordpress backend?</p>