Comparison

  URL="https://raw.githubusercontent.com/kroese/virtual-dsm/master/agent/agent.sh"

  remote_size=$(curl -sIk -m 4 "${URL}" | grep -i "content-length:" | tr -d " \t" | cut -d ':' -f 2)

  [[ "$remote_size" == "" ]] && return

  [[ "$remote_size" == "0" ]] && return

  [ "$remote_size" == "" ] && return

  [ "$remote_size" == "0" ] && return

  SCRIPT=$(readlink -f ${BASH_SOURCE[0]})

  local_size=$(stat -c%s "$SCRIPT")

  [[ "$remote_size" == "$local_size" ]] && return

  [ remote_size -eq local_size ] && return

  if ! curl -sfk -m 10 -o "${TMP}" "${URL}"; then

    echo "$HEADER: curl error" && return