Type Alias PDCallbackFunction 

pub type PDCallbackFunction = Option<unsafe extern "C" fn(userdata: *mut c_void) -> c_int>;

Aliased Type

pub enum PDCallbackFunction {
    None,
    Some(unsafe extern "C" fn(*mut c_void) -> i32),
}

Variants

None

No value.

Some(unsafe extern "C" fn(*mut c_void) -> i32)

Some value of type T.