Re: mixing multisockets and forks

Have you heard of the concept of simplifying to a small test case? Anyway that said AFAIKS the problem is that in your incredibly misnamed new_thread routine you are doing this:

if ( $pid = fork() ) {
    $threads++;  # you mean kids
  return $pid
}
# this is kid code
# kid does socket but.....then......
exit($result);
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So the child process is exiting but you are not decrementing the '$thread' count, at least in the code presented. Nor are you communicating its death to the parent. So the reason you are getting a no children error is simple -> *there are no children* because they have finished but the parent simply does not know it.

At a glance I don't see how you think the IPC between parent and child is going to work, and given the length of your sample and what I find really inaccurate and annoying names (ie a forked kid is not a thread) a glance is all it is going to get. When you fork parent and child get copies of all data and handles. Independent* copies so if the kid does stuff to the data the parents data remains unchanged.

* yes I understand COW.

cheers

tachyon

Comment on Re: mixing multisockets and forks Download Code

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Re: Re: mixing multisockets and forks
by fxmakers (Friar) on Mar 29, 2004 at 00:50 UTC

use POSIX ":sys_wait_h";

$SIG{'CHLD'} = \&REAPER;  # manage moribound children
sub REAPER {
  my $pid = 0;

  while (($pid = waitpid(-1, &WNOHANG)) > 0) { $status{$pid} = $?; }

  $SIG{'CHLD'} = \&REAPER;
}
[download]

use strict;
use POSIX ":sys_wait_h";

$SIG{'CHLD'} = \&REAPER;

sub REAPER {
  my $pid = 0;

  while (($pid = waitpid(-1, &WNOHANG)) > 0) {
    print STDOUT "$pid returned $?\n";
  }

  $SIG{'CHLD'} = \&REAPER;
}

sub new_thread {
  my $result = 0;

  if (my $pid = fork()) {
    return($pid);
  }

  $result = 1;

  exit($result);
}

my $child = &new_thread();
print STDOUT "got a new child: $child\n";

for (;;) {}

1;
[download]

use strict;
use POSIX ":sys_wait_h";
use IO::Socket::INET;

$SIG{'CHLD'} = \&REAPER;

sub REAPER {
  my $pid = 0;

  while (($pid = waitpid(-1, &WNOHANG)) > 0) {
    print STDOUT "$pid returned $?\n";
  }

  $SIG{'CHLD'} = \&REAPER;
}

sub new_thread {
  my $result = 0;

  if (my $pid = fork()) {
    return($pid);
  }

  sleep(3);

  $result = 1;

  exit($result);
}

my %socklist = (); # hash table of sockets
my $bit = '';

# connect to the IRC server
my $socket = &open_socket("tcp", "irc.creatixnet.com", 6667, 3);

sub open_socket {
  my ($proto, $host, $port, $timeout) = (shift, shift, shift, shift);

  my $socket = IO::Socket::INET->new(
    Proto => $proto,
    PeerAddr => $host,
    PeerPort => $port,
    Timeout => $timeout
  );

  if (!$socket) { return(0); }
  return($socket);
}

if (!$socket) { die("can't connect"); }

&add_socket($socket, "IRC");

sub add_socket {
  my ($socket, $type) = (shift, shift);

  $socket->autoflush(1);

  $socklist{$socket}{'sock'} = $socket;
  $socklist{$socket}{'type'} = $type;
  $socklist{$socket}{'fileno'} = $socket->fileno();

  vec($bit, $socklist{$socket}{'fileno'}, 1) = 1;

  return(0);
}

print $socket "USER zxf sdf sdf sdf\n";
print $socket "NICK sdfsdfg\n";
print $socket "JOIN #fx\n";

my $child = &new_thread();
print STDOUT "got a new child: $child\n";

sub loop_socket {
  my $rin = $bit; $rin =~ /[^\0]/ || next;
  my $idx = select($rin, undef, undef, 1);
  my $buffer = "";

  $idx || next;
  $idx > 0 || die($!);

  my %list = %socklist;

  while ($idx && (my ($socket, $value) = each(%list))) {
    $socket = $value->{'sock'};

    if (vec($rin, $value->{'fileno'}, 1)) { $buffer = <$socket>; print
+ STDOUT "IRC: $buffer"; }
  }

  return(0);
}

for (;;) {
  &loop_socket();
}

1;
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