Display the commands required to merge to packet captures and align their time stamps

get-shift.sh

#!/bin/bash
one=$1
two=$2
if [[ $one == "" || $two == "" ]]; then
  echo Display commands to merge two packet captures to the same time
  echo $0 "<cap one> <cap two> <offset>"
  exit 1
fi
offset=$3
if [[ ! $offset > 0 ]]; then
  offset=0
fi
bone=$(basename $one .cap)
btwo=$(basename $two .cap)
startone=$(capinfos -aeS $one|grep Start|tr -s \  \ |cut -d\  -f3)
starttwo=$(capinfos -aeS $two|grep Start|tr -s \  \ |cut -d\  -f3)
if [[ $startone > $starttwo ]]; then
  shift=$(( $startone - $starttwo ))
  echo editcap -t $shift $two $btwo-shifted.cap
  echo mergecap -w $bone+$btwo-merged.cap $one $btwo-shifted.cap
else
  shift=$(( $starttwo - $startone ))
  echo editcap -t $shift $one $bone-shifted.cap
  echo mergecap -w $bone+$btwo-merged.cap $bone-shifted.cap $two
fi