C header files:

- cleanup

src/include/H5Block_io.h

@@ -20,6 +20,10 @@
    @{
 */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
   Write the 3-dimensional field \p name from the buffer pointed to by
   \p buffer to the current step using the previously defined field
@@ -427,5 +431,9 @@ H5Block3dReadVector3dFieldInt32 (
 					     x_buf, y_buf, z_buf, H5T_NATIVE_INT32));
 }
 
+#ifdef __cplusplus
+}
+#endif
+
 ///< @}
 #endif