--- /dev/null
+#!/bin/sh
+# drive_gnuplot syntehsises the commands for driving gnuplot
+
+the_log_file=data
+
+plot_str=" plot 'trunc_data' using 1:3 with linespoints title 'free', '' using 1:4 with linespoints title 'erased'"
+
+echo "set title 'yaffs free space and erased space'"
+
+echo $plot_str
+
+while true; do
+sleep 1
+tail -100 $the_log_file > trunc_data
+echo replot
+done
+