Index: library/mongodb/nsfmongo.c
===================================================================
diff -u -rcef0608bea97458e5dcd87615c9b8ca3fe7b464c -r2fbf1bf87402e8639e772781c5719164e7e55555
--- library/mongodb/nsfmongo.c	(.../nsfmongo.c)	(revision cef0608bea97458e5dcd87615c9b8ca3fe7b464c)
+++ library/mongodb/nsfmongo.c	(.../nsfmongo.c)	(revision 2fbf1bf87402e8639e772781c5719164e7e55555)
@@ -887,6 +887,9 @@
 
 /***********************************************************************
  * GridFile interface
+ *
+ * Currently offsets and sizes are limited to 32bit integers, we should
+ * relax this later.
  ***********************************************************************/
 
 /*
@@ -993,6 +996,22 @@
   return TCL_OK;
 }
 
+/*
+cmd "gridfile::seek" NsfMongoGridFileSeek {
+  {-argName "file" -required 1 -type gridfile}
+  {-argName "offset" -required 1 -type int32}
+}
+*/
+static int 
+NsfMongoGridFileSeek(Tcl_Interp *interp, gridfile *gridFilePtr, int offset) {
+  int pos;
+
+  pos = gridfile_seek(gridFilePtr, offset);
+  Tcl_SetObjResult(interp, Tcl_NewIntObj(pos));
+
+  return TCL_OK;
+}
+
 /***********************************************************************
  * Finally, provide the necessary Tcl package interface.
  ***********************************************************************/