Hello all,
Apparently Tuesday is just as bad. I have this subroutine: 
sub StartErrorGuardian
{
    my ($this, $pm) = @_;
    $this->Log("INFO","CWAPP: Starting error guardian\n");
    $continue_flag = 1;
    if ($this->{bThreadStarted} == 0) {
        $this->{bThreadStarted} = 1;
        my $pid= fork();
        if (not defined $pid) {
            $this->Log("ERROR","CWAPP: Could not start error guardian\
+n");
            return 0;
        } 
        if ($pid == 0) {
            $this->Guardian();
        } else {
            return $pid;
        }
    }
    return 0;
}

[download]
which creates (or should create) a child to handle with the Guardian subroutine. 
sub Guardian
{
my ($this) = @_;
  my $i = 0;
  while (1)
  {
    {#find any message-box with class #32770 [usually infos and errors
+] and press it's child OK button
      @err_window = FindWindowLike(undef, "", "#32770");
      foreach (@err_window)
      {
        SetForegroundWindow($_);
        SetActiveWindow($_);
        PushChildButton( $err_window[$i], "OK", 0.25 );
      PushChildButton( $err_window[$i], "Abort", 0.25 );
      }

    sleep 1;
  }
}

[download]
If I call the first subroutine from a normal script, everything goes just fine. If I make a fork() and call StartErrorGuardian from the child, nothing happens. And I meen literally nothing. The line my $pid= fork() just blocks the script. It does not pass it. I also tried using Parallel::ForkManager and threads but I get the same result.
So, what I would want to do would be to view some process information before the fork() line. Some kind of debugging, as running the script with -d just crashes at the first fork(). Any suggestions?
Thanks.

In reply to multithreaded debugging by Razvanica

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