-void ent_volume_call( world_instance *world, ent_call *call );
-void ent_audio_call( world_instance *world, ent_call *call );
-void ent_ccmd_call( world_instance *world, ent_call *call );
+entity_call_result ent_volume_call( world_instance *world, ent_call *call );
+entity_call_result ent_audio_call( world_instance *world, ent_call *call );
+entity_call_result ent_ccmd_call( world_instance *world, ent_call *call );