Check whether a root file already exists. This resolves issue #5.

patch-control.sh

@@ -153,6 +153,14 @@ done | zenity --progress \
 # Peak the run number
 
 run_number=`get_run_number`
+
+ROOT_FILE=`printf "${DIR}/KM3NeT_%08d.root" ${run_number}`
+ssh ${DAQ_USER}@${DAQ_SERVER} "[ -e ${ROOT_FILE} ]" && {
+  log "A root file for the current run already exists. Run ${run_number} canceled."
+  zenity --error --text="A root file for the current run already exists. Run ${run_number} canceled."
+  exit 1
+}
+
 let "run_duration_seconds = ${run_duration} * 60"
 
 log "Run ${run_number} ready to start. \