How to run gridpack in readonly mode

In order to run the same gridpack multiple times simultaneously, you need to create the gridpack like this:
Then when after you unpack your gridpack on cvmfs,
You have to run the following script:

1) create the gridpack as usual:
  generate p p > t t~
  output MYDIR
  launch
  set gridpack T

2) untar your gridpack and run the following command:
     cd $GRIDPACK/madevent
     ./bin/internal/restore_data default

3) Optional remove all the file ftn26_default.tgz and results_default.dat from the madevent directory
4) set the full madevent directory in readonly mode (either via cvmfs or via a simple chmod)

To run the gridpack you can do the following
mkdir MY_NEW_RUN_X
cd MY_NEW_RUN_X
$GRIDPACK/run.sh ${NB_EVENT} ${SEED}

at the end of the run the directory will only contain an event file.
To keep more details (full log/...) you can edit run.sh to avoid the removal of the file.