Add the "Cactus version" attribute to a datafile indicating that variables

with multiple timelevels should be read in following the new timelevel scheme.

Thanks to Ken Smith for pointing this out.
This closes PR Documentation/1107.


git-svn-id: http://svn.cactuscode.org/arrangements/CactusPUGHIO/IOHDF5/trunk@145 4825ed28-b72c-4eae-9704-e50c059e567d

2 files changed, 20 insertions, 6 deletions

diff --git a/doc/CreateIOHDF5datafile.c b/doc/CreateIOHDF5datafile.c
index 5e1d597..bb1275c 100644
--- a/doc/CreateIOHDF5datafile.c
+++ b/doc/CreateIOHDF5datafile.c
@@ -33,10 +33,13 @@
 #define GLOBAL_ATTRIBUTES_GROUP  "Global Attributes"
 #define CCTK_GF                  2
 
+/* the Cactus version that this datafile is (upwards) compatible with 
+   (versions below beta10 use a different timelevel scheme) */
+#define CACTUS_VERSION  "4.0.b10"
+
 /* a simple macro to do an HDF5 call with return code checking
    in case of an error it will issue an error message and exit */
 #define CHECK_ERROR(hdf5_call)                                                \
-          do                                                                  \
           {                                                                   \
             int _error_code = hdf5_call;                                      \
                                                                               \
@@ -48,7 +51,7 @@
                                 __LINE__, #hdf5_call, _error_code);           \
               return (-1);                                                    \
             }                                                                 \
-          } while (0)
+          }
 
 
  /*@@
@@ -96,6 +99,8 @@ int main (void)
      we are lazy here and only initialize it to zero */
   data = calloc (elements, sizeof (double));
 
+  CHECK_ERROR (stringtype = H5Tcopy (H5T_C_S1));
+
 
   /**************************************************************************/
   /* create a group with attributes describing how the data in this file    */
@@ -127,6 +132,14 @@ int main (void)
                                  dataspace, H5P_DEFAULT));
   CHECK_ERROR (H5Awrite (attr, H5T_NATIVE_INT, &ioproc_every));
   CHECK_ERROR (H5Aclose (attr));
+
+  /* the version of Cactus that this datafile is (upwards) compatible with */
+  CHECK_ERROR (H5Tset_size (stringtype, strlen (CACTUS_VERSION)));
+  CHECK_ERROR (attr = H5Acreate (dataset, "Cactus version", stringtype,
+                                 dataspace, H5P_DEFAULT));
+  CHECK_ERROR (H5Awrite (attr, stringtype, CACTUS_VERSION));
+  CHECK_ERROR (H5Aclose (attr));
+
   CHECK_ERROR (H5Gclose (group));
   CHECK_ERROR (H5Sclose (dataspace));
 
@@ -161,9 +174,6 @@ int main (void)
   /* add the necessary attributes describing the dataset                    */
   /* as a Cactus grid variable                                              */
   /**************************************************************************/
-  CHECK_ERROR (dataspace = H5Screate (H5S_SCALAR));
-  CHECK_ERROR (stringtype = H5Tcopy (H5T_C_S1));
-
   /* the variable's group name (as specified in the interface.ccl file) */
   groupname = "grid::coordinates";
   CHECK_ERROR (H5Tset_size (stringtype, strlen (groupname)));
diff --git a/doc/documentation.tex b/doc/documentation.tex
index d950402..fc0afbc 100644
--- a/doc/documentation.tex
+++ b/doc/documentation.tex
@@ -220,12 +220,16 @@ template for building your own data converter program.\\
           \item Does the file contain chunked or unchunked data ?
           \item How many processors were used to produce the data ?
           \item How many I/O processors were used to write the data ?
+          \item What Cactus version is this datafile compatible with ?
         \end{itemize}
         Such information is put into as attributes into a group named
         {\tt "Global Attributes"}. Since we assume unchunked data here
         the processor information isn't relevant --- unchunked data can
         be fed back into a Cactus simulation running on an arbitrary
-        number of processors.
+        number of processors.\\
+        The Cactus version ID must be present to indicate that grid variables
+        with multiple timelevels should be recovered following the new
+        timelevel scheme (as introduced in Cactus beta 10).
 \end{enumerate}
 
 The example C program goes through all of these steps and creates a datafile