Opens a file.
The fulfilled value in the promise will be the Eina.File*.
open @const { params { @in path: string; @in shared: bool; } return: future<Eina.File>; }
Eina_Future *efl_io_manager_open(const Eo *obj, const char *path, Eina_Bool shared);
true
if the file can be accessed by others, false
otherwise