io/ompio: change default for sharedfp_lazy_open parameter

Revert the logic of io_ompio_sharedfp_lazy_open. The user now has to explicitely
disable shared fp in order for the structures not to be allocated.
Otherwise, resetting the shared fp e.g. in case the file was opened
in append mode will not work correctly, the code could deadlock.

Signed-off-by: Edgar Gabriel <egabriel@central.uh.edu>

ompi/mca/io/ompio/io_ompio_component.c

@@ -36,7 +36,7 @@ int mca_io_ompio_bytes_per_agg = OMPIO_PREALLOC_MAX_BUF_SIZE;
 int mca_io_ompio_num_aggregators = -1;
 int mca_io_ompio_record_offset_info = 0;
 int mca_io_ompio_coll_timing_info = 0;
-int mca_io_ompio_sharedfp_lazy_open = 1;
+int mca_io_ompio_sharedfp_lazy_open = 0;
 
 int mca_io_ompio_grouping_option=5;
 
@@ -193,7 +193,7 @@ static int register_component(void)
                                            &mca_io_ompio_num_aggregators);
 
 
-    mca_io_ompio_sharedfp_lazy_open = 1;
+    mca_io_ompio_sharedfp_lazy_open = 0;
     (void) mca_base_component_var_register(&mca_io_ompio_component.io_version,
                                            "sharedfp_lazy_open",
                                            "lazy allocation of internal shared file pointer structures",