Shorten Framework currently has no callback mechanisms. Until then, did a workaround for the source system.

Plugins/Shorten/ShortenDecoder.mm

@@ -10,8 +10,14 @@
 
 @implementation ShortenDecoder
 
-- (BOOL)open:(NSURL *)url
+- (BOOL)open:(id<CogSource>)source
 {
+	NSURL *url = [source url];
+	if (![[url scheme] isEqualToString:@"file"])
+		return NO;
+	
+	[source close];
+	
 	decoder	= new shn_reader;
 	
 	if (!decoder)
@@ -124,6 +130,10 @@
 		shn_unload(handle);*/
 }
 
+- (BOOL)seekable
+{
+	return YES;
+}
 
 - (NSDictionary *)properties
 {

Plugins/Shorten/ShortenPropertiesReader.mm

@@ -11,13 +11,13 @@
 
 @implementation ShortenPropertiesReader
 
-- (NSDictionary *)propertiesForURL:(NSURL *)url
++ (NSDictionary *)propertiesForSource:(id<CogSource>)source
 {
 	NSDictionary *properties;
 	ShortenDecoder *decoder;
 	
 	decoder = [[ShortenDecoder alloc] init];
-	if (![decoder open:url])
+	if (![decoder open:source])
 	{
 		return nil;
 	}