Just global state. Simple example, a global variable that holds an allocated memory buffer. You initialize it at program startup and tear it down at the end (you can be sloppy and leave out the latter). While the program is running, you re-allocate as needed.

This is better in that it really is a very simple thing to do. There are no possible memory leaks. But what happens is much more explicit - you have precise control, and no bumpy control flow (much nicer for debugging).

But it doesn't have to be memory. If you want to look at my project https://github.com/jstimpfle/learn-opengl (careful - it's not tidied up. But I think it demonstrates my point), most resource state there is global module-wide state. I simply have init_module() and exit_module() pairs that I call from the main function. Problem solved. Not a headache at all.