ndstatus (network devices status check)

#!/bin/bash

#check network device status
#exit codes 0 - device up 1 - device down 2 - none device
#3 - help or wrong parameters

SLNT=0

print_help()
{
    echo "Use "`basename $0`" <device> [-s]"
    echo "<device> - network device name, e.g. eth0"
    echo "-s - silent mode, no console output"
}

#parameters check and set silent mode
if [ $# -eq 0 ]; then
    echo "Wrong parameters!"
    echo
    print_help
    exit 3
else
    if [ $# -eq 2 ]; then
    if [[ "$2" == "-s" ]]; then
        SLNT=1
    else
        echo "Wrong parameters!"
        echo
        print_help
        exit 3
    fi
    fi
fi

#print help
if [[ "$1" == "--help" || "$1" == "-h" ]]; then
    print_help
    exit 3
fi

DEV=$1

# check device exist
DOWN=`ifconfig -a | grep $DEV -c`
if [ $DOWN -eq 0 ]; then
    if [ $SLNT -eq 0 ];then
    echo "Device $DEV: NONE"
    fi
    exit 2
fi

#check up/down status
UP=`ifconfig | grep $DEV -c`
if [ $UP -eq 0 ]; then #device down
    if [ $SLNT -eq 0 ];then
    echo "Device $DEV: DOWN"
    fi
    exit 1
else
    if [ $SLNT -eq 0 ];then
    echo "Device $DEV: UP"
    fi
    exit 0
fi