extern "C" used in skeletons

diff --git a/skeletons/ber_tlv_tag.h b/skeletons/ber_tlv_tag.h
index 51c9a08..60e8668 100644
--- a/skeletons/ber_tlv_tag.h
+++ b/skeletons/ber_tlv_tag.h
@@ -5,6 +5,10 @@
 #ifndef	_BER_TLV_TAG_H_
 #define	_BER_TLV_TAG_H_
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 enum asn_tag_class {
 	ASN_TAG_CLASS_UNIVERSAL		= 0,	/* 0b00 */
 	ASN_TAG_CLASS_APPLICATION	= 1,	/* 0b01 */
@@ -49,4 +53,8 @@
  */
 size_t ber_tlv_tag_serialize(ber_tlv_tag_t tag, void *bufptr, size_t size);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif	/* _BER_TLV_TAG_H_ */