How can I create a hook into an external module

Question

I want to be able to alter a function inside another module like a hook, but I'm not sure if that's what it's called. I want to alter a function inside another module from my module without changing the external modules code.

This is in version 7.x.

Thanks Frank N.

Answer 1

PHP offers no mechanism to do that.

If the external function isn't a hook (i.e. it doesn't use module_invoke() or drupal_alter() to gather data from other modules) then the only thing you can do is patch the function in the external file.