Re: POE newbie question

P Dobranski wrote:
> POE::Kernel::yield is sort of a shortcut for 'post'. 
> You 'yield' an event in the current session.
> It is the same as 'post'ing the event to the current session.
>
> $kernel->yield('some_event_handler');
>
> is roughly the same as
> $kernel->post($my_session, 'some_event_handler');
>
> (assuming both statements happen in the same session).
>
> select_read/select_write allow you to get events when a file 
> descriptor becomes ready to read or write without you having to manage 
> your own select() loops.
> On 2/22/07, Fei Liu <feiliu@xxxxxxxxxxxxxxx> wrote:
> > Hi group, just wondering what's the difference between
> > POE::Kernel::select_read/write method and POE::Kernel::yield method? How
> > should I use select_read/select_write? Do they do anything special about
> > the events that they select? Thanks,
> >
> > Fei
Thanks for your reply. I was reading Rocco's tutorial 
(http://poe.perl.org/?Evolution_of_a_POE_Server) on POE and my question 
came up when he first introduced POE framework to replace the original 
non-blocking tcp echo server. In the example no Wheel or 
Component::Server::TCP were used, it was basic POE::Session.
POE::Session->create
 ( inline_states =>
     { _start => \&server_start,
       event_accept => \&server_accept,
       event_read   => \&client_read,
       event_write  => \&client_write,
       event_error  => \&client_error,
     }
 );

sub server_start {
   my $server = IO::Socket::INET->new
     ( LocalPort => 12345,
       Listen => 10,
       Reuse  => "yes",
     ) or die "can't make server socket: $@\n";

   $_[KERNEL]->select_read( $server, "event_accept" );
}

Here it seems select_read works sort of like yield, doesn't it? It 
yields to event_accept handler? Quote 'The _start handler creates the 
server socket and allocates its event generator with select_read()", 
what's a event generator and what does it do?
Another thing confusing me here is that there seems to be a total of one 
session in this echo server implementation, how can it handle mutliple 
clients?
Sorry for so many questions, I can use POE just fine but I want to 
understand what's going on under the hood.
Fei