download large files in chunks

download-chunker.sh

#! /bin/bash
LARGE_FILE_URL="http://vatic2.stanford.edu/stanford_campus_dataset.zip"
APPROX_SIZE=`echo "69*1024*1024*1024"| bc`
CHUNKSIZE=`echo "128*1024*1024" | bc`
NCHUNKS=`echo "1+ (($APPROX_SIZE)/($CHUNKSIZE))" | bc`
STARTCHUNK="1"
OUTDIR="/media/debanjan/xxx"
OUTFILE="stanford_campus_dataset.zip"
SLEEP_INTERVAL="10"
for ichunk in $(seq -f '%05g' 1 $NCHUNKS);
do
  from=`echo "($ichunk-1)*$CHUNKSIZE" | bc`
  to=`echo "$ichunk*$CHUNKSIZE - 1"| bc`
  curl --range "$from-$to" "$LARGE_FILE_URL" -o "$OUTDIR/$OUTFILE.$ichunk" 
done