my $domain_file;
FILE:  foreach (@domain_files)
{
    $domain_file = $_;
    print "\tLooking in domain file $domain_file\n" if (DEBUG == 2);
    open DOMAIN_FILE, $domain_file
        or die "Could not open domain file $domain_file:  $!";

    while () #! Could use globbing here...
    {
        if (m/$aname_regex/)
        {
            $aname = $1;
            print "\tFound A name:  $aname in file $domain_file\n" if
DEBUG;
            #There's only one A name for a given host, so
            #stop checking files...
            last FILE;  #*Trouble!  foreach iterator is not reset.
        }
    }
}

##</code><code>##

FILE:  for (my $i = 0; $i <= $#domain_files; $i++)
{
    $domain_file = @domain_files[$i];
    print "\tLooking in domain file $domain_file\n" if (DEBUG == 2);
    open DOMAIN_FILE, $domain_file
        or die "Could not open domain file $domain_file:  $!";

    while () #! Could use globbing here...
    {
        if (m/$aname_regex/)
        {
            $aname = $1;
            print "\tFound A name:  $aname in file $domain_file\n" if DEBUG;
            last FILE;
        }
    }
}