ssh-purge-host

#!/bin/bash

LINE=$1
KNOWN_HOSTS=~/.ssh/known_hosts

usage() {
  cat <<-EOM

  Usage: ssh-purge-host <line no>

EOM
}

if test -z $LINE; then
  usage
  exit
fi

if ! test -e $KNOWN_HOSTS; then
  echo "$KNOWN_HOSTS does not exist"
  exit 1
fi

MSG="$(sed -n "${LINE}p" $KNOWN_HOSTS | cut -d ' ' -f 1) removed"
sed -i '' "${LINE}d" $KNOWN_HOSTS
RESULT=$?

if test $RESULT -eq 0; then
  echo $MSG
  exit 0
else
  echo "Something went wrong"
  exit $RESULT
fi