Thanks Rocco you are right. I came across the solution myself last night after discovering all the POE ASSERT settings. Trawled the stats at the end - could see many POE::Wheel::Run "select stdout" activities but nothing that was calling the StdOut Event Handler. So I removed the StdoutFilter and now I'm getting to see all the output from the child process. Now I just have to work out why POE::Filter::Reference was being stalled.
Am I right in thinking that if the child sends anything on STDOUT that isn't POE::Filter::Reference text then it stalls the comms for the lifetime of that child process not just that instance of POE::Wheel::Run "select stdout"?? If this is the case then I maybe have some untrapped output I need to chase down. Which I guess I can do by leaving the filter off. Simon Simon Taylor Development Team Lead NMS Applications Network Managed Services Nortel Networks (e) s...@nortel.com (p) +44 1279 402291 ESN 6 742 2291 (m) +44 7740 533743 ESN 6 748 3743 (yim) setuk_nortel -----Original Message----- From: Rocco Caputo [mailto:rcap...@pobox.com] Sent: 09 November 2009 23:04 To: POE Mailing List Subject: Re: Not seeing anything back out of STDOUT This can happen with POE::Filter::Reference if the child process displays some non-POE::Filter::Reference text. POE::Filter::Reference does its best to interpret the child process' output as legal data, and it patiently awaits the completion of a bad record. The socket connection is made by creating the socket in the parent process, then sharing it between the parent and child after the fork() duplicates it. No client/server shenanigans are performed to set up the connection. It could be something else, but I can't tell without seeing more code. :) -- Rocco Caputo - rcap...@pobox.com On Nov 9, 2009, at 06:05, Simon Taylor wrote: > Using POE::Wheel::Run to create forked children. > > As soon as i fork them off I try and send some output back to the > parent > but i never see it arrive. > > At this point STDOUT in the child is not a TTY and lsof indicates > its a > socket connection. > > > > new_batch 30624 sdu 0u unix 0x00000100376a7680 9949033 socket > new_batch 30624 sdu 1u unix 0x00000100376a7680 9949033 socket > new_batch 30624 sdu 11u unix 0x00000100376a7680 9949033 socket > > > > I'm thinking this is possibly how POE is connecting the child output > with that of the parent. > > > > I've run POE in Debug mode and im not seeing any calls into the Event > Handler for STDOUT. > > > > Setup as follows - STDERR seems to be working ok. > > Any assistance appreciated. > > > > > > sub StartTasks { > > =Head3 _start > > Function called when POE wants to start tasks > > Shouldnt start any more than MAX_CONCURRENT_TASKS > > When it does it spawns children > > Event handlers allow information to be passed back to the parent > process > > Mapping between state and function is done in the object states line > in > the POE::Session->create in _IterateChildrenParallel > > > > =cut > > my ($kernel, $self, $heap) = @_[KERNEL, OBJECT]; > > my ($child, $task); > > $self->{_logger}->debug("Enter/Reentry"); > > while (keys(%{$heap->{task}}) < MAX_CONCURRENT_TASKS) { > > if (ref($self->{_children}) eq "ARRAY"){ > > $child = shift @{$self->{_children}}; > > last unless defined $child; > > $self->{_logger}->debug("ARRAY "."Child = $child"); > > $task = POE::Wheel::Run->new( > > Program => sub {local *__ANON__ = > "_StartTasksProgramSub"; > > $self->_CreateChild($child); > > }, > > StdoutFilter => POE::Filter::Reference->new(), > > StdoutEvent => "TaskResult", > > StderrEvent => "TaskError", > > CloseEvent => "TaskDone", > > ); > > $heap->{task}->{$task->ID} = $task; > > $self->{_logger}->info("Created child Task/PID > ".$task->ID."/".$task->PID); > > $_[KERNEL]->sig_child($task->PID, 'sig_child'); > > > > # Wheel events include the wheel's ID. > > $_[HEAP]{children_by_wid}{$task->ID} = $task; > > > > # Signal events include the process ID. > > $_[HEAP]{children_by_pid}{$task->PID} = $task; > > > > > > > > } elsif (ref($self->{_children}) eq "HASH") { > > $self->{_logger}->debug("HASH "."Child = $child"); > > $self->_CreateChild($child); > > } else { > > $self->{_logger}->debug("SCALAR "."Child = $child"); > > $self->_CreateChild($child); > > } # If end > > } # While end > > } > > > > sub TaskResult { > > my ($self,$result) = @_[OBJECT, ARG0]; > > $self->{_logger}->info("ID/PID/Result ID: $result->{taskid} : > $result->{pid} :$result->{status}\n"); > > > > my %sec_status = %{$result->{section_status}}; > > > > foreach my $key (%sec_status){ > > $self->{_logger}->info("$sec_status{$key}\n"); > > } > > > > } > > > > > > Simon Taylor > > Development Team Lead NMS Applications > > Network Managed Services > > Nortel Networks > > > > (e) s...@nortel.com > > (p) +44 1279 402291 ESN 6 742 2291 > > (m) +44 7740 533743 ESN 6 748 3743 > > (yim) setuk_nortel > > >
