Function glib_sys::g_ucs4_to_utf16

pub unsafe extern fn g_ucs4_to_utf16(str: *const u32,
                                     len: c_long,
                                     items_read: *mut c_long,
                                     items_written: *mut c_long,
                                     error: *mut *mut GError)
                                     -> *mut u16