extern "C" used in skeletons


git-svn-id: https://asn1c.svn.sourceforge.net/svnroot/asn1c/trunk@943 59561ff5-6e30-0410-9f3c-9617f08c8826
diff --git a/skeletons/der_encoder.h b/skeletons/der_encoder.h
index cb784d1..9e7867d 100644
--- a/skeletons/der_encoder.h
+++ b/skeletons/der_encoder.h
@@ -7,6 +7,10 @@
 
 #include <asn_application.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct asn_TYPE_descriptor_s;	/* Forward declaration */
 
 /*
@@ -56,4 +60,8 @@
 		void *app_key
 	);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif	/* _DER_ENCODER_H_ */