FAQ-1038 Why do I get a E32USER-CBase 44 panic when I try to use a CMdaAudioPlayerUtility?


FAQ-1038 Why do I get a E32USER-CBase 44 panic when I try to use a CMdaAudioPlayerUtility?

» Symbian OS » Developer Knowledgebase » FAQ-1038

Classification:	C++	Category:	Multimedia
Created:	04/27/2004	Modified:	05/06/2004
Number:	FAQ-1038
Platform:	Symbian OS v6.0, Symbian OS v6.1, Symbian OS v7.0, Symbian OS v7.0s, Symbian OS v8.0

Question:
Why do I get a E32USER-CBase 44 panic when I try to use a CMdaAudioPlayerUtility?

Answer:
You probably have not started an active scheduler on the thread on which you are making the call. The main thread of an application has a default active scheduler provided by the application architecture. But multimedia code will often execute on another (background) thread. For this reason, not just audio but any of the utilities provided through Symbian's multimedia framework such as video, image manipulation and/or MIDI is likely to require an active scheduler to be explicitly installed and started.

It is a common experience that JNI (Java Native Interface) developers encounter this problem since the JNI environment on Symbian OS does not provide a default active scheduler for Java apps, even on the "main" Java thread (although it does incidentally provide a default CleanupStack).