diff --git a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs/include/hdfs/hdfs.h b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs/include/hdfs/hdfs.h
index c1515d7f2ac..3940e0e9b37 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs/include/hdfs/hdfs.h
+++ b/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs/include/hdfs/hdfs.h
@@ -408,6 +408,7 @@ extern  "C" {
      *         complete before proceeding with further file updates.
      *         -1 on error.
      */
+    LIBHDFS_EXTERNAL
     int hdfsTruncateFile(hdfsFS fs, const char* path, tOffset newlength);
 
     /**