get_ip.txt

#!/bin/bash
domain_ip=/tmp/a.txt
collect_ip=/tmp/b.txt
# Specify DNS server
dnsserver="119.29.29.29"
# function to get IP address
function get_ipaddr {
    local hostname=$1
    local query_type=A
    ip_address=""
    # use host command for DNS lookup operations
    host -t ${query_type} "${hostname}" ${dnsserver} &>/dev/null
    if [ "$?" -eq "0" ]; then
        # get ip address
        ip_address="$(host -t ${query_type} "${hostname}" ${dnsserver} | awk '/has.*address/{print $NF; exit}')"
    else
        echo "############"
    fi
    # display ip
    echo "$ip_address"
}
true >$collect_ip
awk 'BEGIN{while (a++<50) s=s "-"; print s,"testing output only one",s}'
IFS=' ' read -r -a domain_array <<< "$(cat < $domain_ip|awk '{print$1}')"
echo "${domain_array[@]}"
awk 'BEGIN{while (a++<50) s=s "-"; print s,"testing output finished",s}'

awk 'BEGIN{while (a++<50) s=s "-"; print s,"testing read from file",s}'
IFS=' '
while read -r domain_array ip_array;do
    echo "domain_array is ${domain_array}"
    get_ipaddr "${domain_array}"
    echo "${domain_array}" "$(get_ipaddr "${domain_array[$i]}")" >>$collect_ip
    echo "ip_array is ${ip_array}"
done < $domain_ip
awk 'BEGIN{while (a++<50) s=s "-"; print s,"get_ipaddr and collect ip finished",s}'
cat $collect_ip