Index: trunk/ppMerge/src/ppMergeData.c
===================================================================
--- trunk/ppMerge/src/ppMergeData.c	(revision 7073)
+++ trunk/ppMerge/src/ppMergeData.c	(revision 7759)
@@ -9,4 +9,11 @@
     )
 {
+    if (data->files) {
+        for (long i = 0; i < data->files->n; i++) {
+            psFitsClose(data->files->data[i]);
+            data->files->data[i] = NULL;
+        }
+        psFree(data->files);
+    }
     psFree(data->in);
     psFree(data->out);
@@ -23,4 +30,5 @@
 
     data->numCells = 0;
+    data->files = NULL;
     data->in = NULL;
     data->out = NULL;