Guard headers tool.
diff --git a/examples/pubsub/publisher.h b/examples/pubsub/publisher.h
index 2d64a2a..c90406f 100644
--- a/examples/pubsub/publisher.h
+++ b/examples/pubsub/publisher.h
@@ -31,8 +31,8 @@
*
*/
-#ifndef __GRPCPP_EXAMPLES_PUBSUB_PUBLISHER_H_
-#define __GRPCPP_EXAMPLES_PUBSUB_PUBLISHER_H_
+#ifndef GRPC_EXAMPLES_PUBSUB_PUBLISHER_H
+#define GRPC_EXAMPLES_PUBSUB_PUBLISHER_H
#include <grpc++/channel_interface.h>
#include <grpc++/status.h>
@@ -64,4 +64,4 @@
} // namespace examples
} // namespace grpc
-#endif // __GRPCPP_EXAMPLES_PUBSUB_PUBLISHER_H_
+#endif // GRPC_EXAMPLES_PUBSUB_PUBLISHER_H