dl.sh

#!/bin/bash

export USER=hoge
export PASSWORD=fuga
export URLBASE=ftp://ftp.example.com

function download() {
  wget --ftp-user $USER --ftp-password $PASSWORD $URLBASE/$1
}

export -f download

if [[ $1 =~ \.md5$ ]]; then
  awk '{ print $2 }' $1 | xargs -I % bash -c "download %"
  md5sum -c $1
else
  download $1
fi