1#!/bin/sh 2 3filename=${1:-sparse.dat} 4size=${2:-100M} 5 6echo "start" > $filename 7dd if=/dev/zero of=$filename bs=1 count=0 seek=$size 2>/dev/null 8echo "end" >> $filename 9 10size="`du --block-size=1 --apparent-size ${filename} | cut -f 1`" 11realsize="`du --block-size=1 ${filename} | cut -f 1`" 12 13printf "$filename created.\n" 14printf "size=%s\n" "$size" 15printf "realsize=%s\n" "$realsize" 16 17if [ "$realsize" -gt "$size" ]; then 18 printf "ERROR: realsize has to be smaller than size.\n" 19 exit 1 20fi 21