Ome thing that I al struggling at the moment is how to don’t free objects that will need to be managed by the C part in your rust code.
If you are writing a callback you will most likely get a pointer from C that you use for doing whatever, then, before to exit you may want or not to free such pointer.
If you don’t want to free the pointer it get hairy quite quickly.
This is a comment I’ve heard several times, but I’m not sure which bits people are struggling to understand and how to teach the concepts properly.
I’ve personally found that applying Rust’s concepts of ownership and lifetimes to my C/C++ code works really well (i.e. pretend to be the borrow checker or imagine where
rustc would normally insert calls to
drop()), but other people will probably have their own way of understanding things. A hefty dose of the KISS principle also helps when I start trying to be too smart for my own good
Can you think of an example where ownership and lifetimes have gotten confusing when using
unsafe or dealing with FFI?