Hello Monks,

I'm seeking for you wisdom and hope that someone can help me a bit.

I wrote a little daemon that executes programs with IPC::Open3 and intercepts the output from stdout and stderr. IO::Select is used to check if a handle is ready and alarm() for timeouts within eval{}.

The daemon is running very nice on linux, but unfortunately not on windows.

Now I was searching for another solution and thought about to use threads.

In the following example a thread is created to execute a program. The parent waits until $timeout and then detach the thread and kills the process that is maybe still running. 

#!perl.exe
use strict;
use warnings;
use threads;
use threads::shared;
use Data::Dumper;
use IPC::Open3;
use Symbol;

my %data : shared;
my $timeout = 3;
my $command = "perl test.pl";
my $tid = threads->create(sub { execute($command) });

while (--$timeout) {
    if ($tid->is_joinable) {
        $tid->join;
        last;
    }
    sleep 1;
}

if ($timeout == 0) {
    if ($data{pid}) {
        kill -9, $data{pid};
    }
    $tid->detach;
    $data{timedout} = 1;
}

print Dumper(\%data);

sub execute {
    my $in  = Symbol::gensym();
    my $out = Symbol::gensym();
    my $err = Symbol::gensym();
    my $pid = open3($in, $out, $err, @_);
    close $in;
    $data{pid} = $pid;
    # sorry for that dirty handling of $out and $err :-)
    # it was just a hack for tests
    $data{stdout} = do { local $/; <$out> };
    $data{stderr} = do { local $/; <$err> };
    close $out;
    close $err;
    threads->exit;
}

[download]
Now my question to you is: could it be simplier? I don't know if my code example is too much dirty, because I haven't the finest idea of windows.

I would be very pleased for your wisdom.

Cheers
Jonny

Edit: a short code fix

In reply to Windows, threads and IPC::Open3 by bloonix

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