pub enum c_void {}Type used to construct void pointers for use with C.
This type is only useful as a pointer target. Do not use it as a
return type for FFI functions which have the void return type in
C. Use the unit type () or omit the return type instead.
Prefix searches with a type followed by a colon (e.g.
fn:) to restrict the search to a given type.
Accepted types are: fn, mod,
struct (or str), enum,
trait, typedef (or
tdef).