#!/usr/bin/perl -w

#user configuration begin#

$mailprg = "/usr/sbin/sendmail";         #path to your mail program
$delay = 0.25;                     #delay in seconds
$from = 'Coname<somename@domain.com>';         #from address in your m
+ail
$subject = 'Trial send';             #subject of newsletter. u can add
+ the spl code $USERNAME$
$maildata = "mail.dat";                #mail address file
$msgtemplate = "message.template";        #message template file

#user configuration end#

if(@ARGV){
    $i = 0;
    while($ARGV[$i]){
        if($ARGV[$i] eq "--help"){
            print "Command Line Options:\n\n";
            print "-t\tTest how the message will be formatted\n";
            print "-d\tData file listing the email addresses\n";
            print "-m\tMessage template file\n";
            print "-s\tSubject\n";
            print "-f\tFrom address. Quote for security reasons\n";
            die "\nMore information at indiWiz.com\n";
        }
        elsif($ARGV[$i]=~/^-/){
            $arr = substr($ARGV[$i],1,1);
            if($arr eq "d"){
                $maildata = $ARGV[$i+1];
                $i+=2;
            }
            elsif($arr eq "m"){
                $msgtemplate = $ARGV[$i+1];
                $i+=2;
            }
            elsif($arr eq "t"){
                $testflag = 1;
                $i++;
            }
            elsif($arr eq "s"){
                $subject = $ARGV[$i+1];
                $i+=2;
            }
            elsif($arr eq "f"){
                $from = $ARGV[$i+1];
                $i+=2;
            }
            else{
                die "Wrong argument!";
            }
        }
    }
}

open TEMPLATE, $msgtemplate || die "Cannot open template file!\n";
while(<TEMPLATE>){
    $msg .= $_;
}
close TEMPLATE || die "Cannot close template file!\n";

open MAILFILE,"$maildata" || die "Cannot open data file!\n";
while(<MAILFILE>){
    chomp($_);
    @arr = split(/\@/,$_);
    $arr[0] = ucfirst($arr[0]);
    $tmp = $msg;
    $tmp =~ s/\$USERNAME\$/$arr[0]/g;
    $subject =~ s/\$USERNAME\$/$arr[0]/g;
    $temp = "To: $arr[0]<$_>\n";
    $temp .= "From: $from\n";
    $temp .= "Subject: $subject\n\n\n";
    $temp .= $tmp;
    if($testflag){
        print $temp;
        last;
    }
    else{
        open MAILPRG,"|$mailprg -t" || die "Cannot open mail program!\
+n";
        print MAILPRG $temp;
        close MAILPRG || die "Cannot close mailprogram!\n";
    if($delay < 0){
        $delay = 1;
        sleep $delay;
    }
    elsif($delay < 1){
        select(undef,undef,undef,$delay);
    }
    else{
            sleep $delay;
    }
    print $_,"\n";
    }
}
close MAILFILE || die "Cannot close data file!\n";
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Janitored by Arunbear - added readmore tags, as per Monastery guidelines