Function erlang_nif_sys::erlang_nif_sys_api::enif_map_iterator_is_head

pub unsafe extern "C" fn enif_map_iterator_is_head(
    env: *mut ErlNifEnv, 
    iter: *mut ErlNifMapIterator
) -> c_int

See enif_map_iterator_is_head in the Erlang docs.