#7 Merge github patch

src/core.rs

@@ -364,7 +364,22 @@ pub struct EventManager<'a> {
 }
 
 impl<'a> EventManager<'a> {
-    pub fn attach<F>(&self, event_type: EventType, callback: F) -> Result<(), InternalError>
+    pub fn detach(&self, event_type: EventType, registered_callback: *mut c_void) {
+        unsafe {
+            sys::libvlc_event_detach(
+                self.ptr,
+                event_type as i32,
+                Some(event_manager_callback),
+                registered_callback
+            )
+        }
+    }
+
+    pub fn attach<F>(
+        &self,
+        event_type: EventType,
+        callback: F,
+    ) -> Result<*mut c_void, InternalError>
     where
         F: Fn(Event, VLCObject) + Send + 'static,
     {
@@ -372,17 +387,19 @@ impl<'a> EventManager<'a> {
         let callback: Box<Box<dyn Fn(Event, VLCObject) + Send + 'static>> =
             Box::new(Box::new(callback));
 
+        let raw = Box::into_raw(callback) as *mut c_void;
+
         let result = unsafe {
             sys::libvlc_event_attach(
                 self.ptr,
                 event_type as i32,
                 Some(event_manager_callback),
-                Box::into_raw(callback) as *mut c_void,
+                raw,
             )
         };
 
         if result == 0 {
-            Ok(())
+            Ok(raw)
         } else {
             Err(InternalError)
         }