C API design: Who should allocate? [closed]

Answer 1

I would go for (1) with one simple extension, that is to have your _init function always return the pointer to the object. Your pointer initialization then may just read:

myStruct *s = myStruct_init(malloc(sizeof(myStruct)));

As you can see the right hand side then only has a reference to the type and not to the variable anymore. A simple macro then gives you (2) at least partially

#define NEW(T) (T ## _init(malloc(sizeof(T))))

and your pointer initialization reads

myStruct *s = NEW(myStruct);