Shell Programming and Scripting

mail -s "<subject>" "<delivery list>" "matter"

mail -s "my subject" "id1@c.com id2@c.com id3@c.com" "Hey! i m mailing u all"

#!/bin/bash

file="inputfile"
domain="blahblah.com"

for local in $(awk '{print $1}' <$file)
do
        address_list="$address_list $local@$domain"
done

echo "address list is [$address_list]"

echo "Hello this is body of the email" | mailx -s "Subject" $address_list

if [ -n $(echo $address_list | awk '/^(\ )*([A-Za-z0-9_-]+(\.[A-Za-z0-9_-]+)*@([A-Za-z0-9_-]+\.)+[A-Za-z]+((\ )+[A-Za-z0-9_-]+(\.[A-Za-z0-9_-]+)*@([A-Za-z0-9_-]+\.)+[A-Za-z]+)*)(\ )*$/ {print}')" ];then
       # Valid email list
       mailx -s "subject" $address_list < ./email_contents
else
       # Email list problem
       echo "WARNING: Email address list problem [ $address_list ]"
       ....other stuff....
fi

 # cat /etc/aliases
 maillist: user1@blah.com,user2@blah.com,user3@blah.com