use strict;
use Mail::Util ();

defined $ARGV[0] && -f $ARGV[0] or die 'invalid inbox.';

foreach (Mail::Util::read_mbox($ARGV[0])) {
    open(PIPE, "|procmail -m $ENV{HOME}/.procmailrc")
             or die ("cannot start filtering : $!");
    map {print PIPE} @$_;
    close(PIPE);
}