Hi Leostereo,

Sometimes, a given CPAN module maybe multi-process unsafe regarding DESTROY and END blocks. From testing, that seems to be the case with IO::Socket::INET::Daemon or perhaps a dependency. You were close otherwise.

# change this statement
my $pid = $pm->start and next ;

# to the following
my $pid = $pm->start and return !0 ;  # return 1 works too

[download]

The code now looks like this.

use POSIX ();

...

my $pm = Parallel::ForkManager->new(10);
   $pm->set_waitpid_blocking_sleep(0);

my $host = new IO::Socket::INET::Daemon(
    host => 'localhost',
    port => 1000,
    timeout => 20,
    callback => {
        data => \&data,
    },
);

$host->run;

$pm->wait_all_children;

sub data{
    my ($io, $host) = @_;
    my $line = $io->getline;
    return 0 unless $line;
    chomp($line);

    if ($line =~ m/$RE{net}{IPv4}{-keep}/) {
        my $ip = $1;
        print "I got ip $ip\n";
        my $pid = $pm->start and return !0;
        fork_work($ip);
        $pm->finish; # not reached due to calling POSIX::_exit
    }

    print "not a good line:", $line;
    return !0;
}

sub fork_work {
    my ($ip) = @_;
    print "working from new child - $ip\n";

    # A given CPAN module maybe multi-process unsafe regarding
    # DESTROY and END blocks. Fortunately, there's a way around it.

    POSIX::_exit(0);
}

[download]

Another possibility is having background workers poll the IP from a queue, not shown here due to lack of time.

Regards, Mario

In reply to Re: IO::Socket::INET::Daemon and Parallel::ForkManager working together by marioroy
in thread IO::Socket::INET::Daemon and Parallel::ForkManager working togheter by leostereo

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