Question

I have several struct: edge, vertex, graph in my library.
I want to hide body of that structs from user (user have to use API), so in header file (eg. edge.h) I’ve just put:

typedef struct edge edge_t;

And definition of edge struct is in edge.c

struct edge {...};

That works fine, but I want don’t want to hide struct’s body from my own code. I want to use in edge.c:

vertex_t v;
v.some_attribute = x;

Now I get dereferencing pointer to incomplete type errors, is it possible to fix that?
Is there any other option that use accessors (like user) for all struct elements?

Answer 1

If you need to use the structure from other source files, they need the complete definition of the structure. So the solution is to put struct edge { /* ... */ } in the header file as well, and include the header whenever you need to.