写脚本遇到的问题（一）

#!/bin/bash
# Name: optind.sh
# Description:
# Author:
# Version: 0.0.1
# Date: 2016-05-12 10:02:22
# Usage:
show_ip() {
# judge whether eth exists.
    if ! ifconfig | grep -o "^[^[:space:]]\{1,\}" | cut -d: -f 2 | grep $1 &> /dev/null; then
        return 1
    fi
# print
    echo -n "$1: "
    ifconfig $1 | grep -o "inet addr:[0-9\.]\{7,\}" | cut -d: -f 2
}
show_eth() {
# judge whether ip exists.
    if ! ifconfig | grep -o "inet addr:[0-9\.]\{7,\}" | grep $1 &> /dev/null; then
        return 2
    fi
# print
    echo -n "$1: "
    ifconfig | grep -B 1 $1 | grep -o "^[^[:space:]]\{1,\}"
}
usage() {
    echo "getinterface.sh [-i inerface| -I ip]"
}

case $1 in
    -i | -I)
    while getopts ":i:I:" opt;do
        case $opt in
        i)
            show_ip $OPTARG
            [ $? -ne 0 ] && echo "wrong ethenet card"
            ;;
        I)
            show_eth $OPTARG
            [ $? -ne 0 ] && echo "wrong ip"
            ;;
        *)
            usage
            ;;
         esac
    done
    ;;
    *)
        usage
        ;;
esac

#!/bin/bash
# Name: getinterface.sh 
# Description:
# Author:
# Version: 0.0.1
# Date: 2016-05-12 10:02:22
# Usage:
show_ip() {
# judge whether eth exists.
# 修改1
    if ! ifconfig | grep -o "^[^[:space:]]\{1,\}" | cut -d: -f 2 | grep -E "\b$1\b" &> /dev/null; then
        return 1
    fi
# print ip
    echo -n "$1: "
    ifconfig $1 | grep -o "inet addr:[0-9\.]\{7,\}" | cut -d: -f 2
}
show_eth() {
# judge whether ip exists.
# 修改2
    if ! ifconfig | grep -o "inet addr:[0-9\.]\{7,\}" | grep "$1\b" &> /dev/null; then
        return 2
    fi
    echo -n "$1: "
    ifconfig | grep -B 1 $1 | grep -o "^[^[:space:]]\{1,\}"
}
usage() {
    echo "getinterface.sh [-i interface| -I ip]"
}

case $1 in
    -i | -I)
    while getopts ":i:I:" opt;do
        case $opt in
        i)
            show_ip $OPTARG
            [ $? -ne 0 ] && echo "wrong ethenet card"
            ;;
        I)
            show_eth $OPTARG
            [ $? -ne 0 ] && echo "wrong ip"
            ;;
        *)
            usage
            ;;
         esac
    done
    ;;
    *)
        usage
        ;;
esac