perl -p -e '$\+=$_}{' ##

##

LINE: while (defined($_ = )) {
    # Your code here
}
continue {
    die "-p destination: $!\n" unless print $_;
}

##

##

LINE: while (defined($_ = )) {
    $\ += $_;
} 
{ }
continue {
    die "-p destination: $!\n" unless print $_;
}