#! perl

use IO::Select;

my %pids;
my $s = IO::Select->new();

my @proc = (qw(C M));

for ( <@proc> ) {
    my $cmd = "dir $_:";
    print "this is my cmd: $cmd \n\n";
    my $pid = open my $fh, "-|", $cmd
        or warn "Could not fork&open $cmd: $!"
        and next;

    $pids{$fh} = [ $pid, $_ ];
    $s->add($fh);
}

while (my @ready = $s->can_read) {
    for my $fh (@ready) {
        if (eof $fh) {
            delete $pids{$fh};
            $s->remove($fh);
            next;
        }

        my $line = <$fh>;
        if ($line =~ /Rational/) {
            chomp $line;
            print "Found 'Rational' in '$line' from $pid{$fh}[1]\n";
            kill 15, values %pids;
        }
    }
}