1 files changed, 6 insertions, 0 deletions
diff --git a/src/ioGH.h b/src/ioGH.h
index 998e6bf..7b5b16f 100644
--- a/src/ioGH.h
+++ b/src/ioGH.h
@@ -16,6 +16,10 @@ extern "C"
 {
 #endif
 
+/* advertise that this is the new version of this API, which has 'alias'
+ * members in the grid extension */
+#define IOUTIL_IOGH_HAS_ALIAS 1
+
 
 /* IOUtil's GH extension structure */
 typedef struct
@@ -36,6 +40,8 @@ typedef struct
   CCTK_INT *do_inVars;   /* flags indicating to read in variable i with
                             iteration number do_inVars[i] (or -1 to read
                             the last iteration */
+  const char **alias;    /* name under which a variable appears in data files.
+                            If NULL, use CCTK_FullName() */
 } ioGH;