1. cat /proc/net/dev | grep eth0 | sed -e "s/\(.*\)\:\(.*\)/\2/g" | awk '{print $1 }'
    2. sed -e "s/\(.*\)\:\(.*\)/\2/g"
    3. \1:代表:之前的/\(.*\)
    4. \2:代表:之后的/\(.*\)