Convert tabs to spaces.
diff --git a/ndn-cpp/c/encoding/binary-xml-interest.h b/ndn-cpp/c/encoding/binary-xml-interest.h
index a1c9631..e8c955b 100644
--- a/ndn-cpp/c/encoding/binary-xml-interest.h
+++ b/ndn-cpp/c/encoding/binary-xml-interest.h
@@ -4,14 +4,14 @@
  */
 
 #ifndef NDN_BINARYXMLINTEREST_H
-#define	NDN_BINARYXMLINTEREST_H
+#define NDN_BINARYXMLINTEREST_H
 
 #include "../errors.h"
 #include "../interest.h"
 #include "binary-xml-encoder.h"
 #include "binary-xml-decoder.h"
 
-#ifdef	__cplusplus
+#ifdef __cplusplus
 extern "C" {
 #endif
 
@@ -19,7 +19,7 @@
 
 ndn_Error ndn_decodeBinaryXmlInterest(struct ndn_Interest *interest, struct ndn_BinaryXmlDecoder *decoder);
 
-#ifdef	__cplusplus
+#ifdef __cplusplus
 }
 #endif