pickle problem

[Marc 'BlackJack' Rintsch]

On Thu, 08 May 2008 23:35:04 +0200, Hrvoje Niksic wrote:

> Marc 'BlackJack' Rintsch <bj_666 at gmx.net> writes:
> 
>> On Thu, 08 May 2008 08:55:35 -0700, krustymonkey wrote:
>>
>>> The thing is, I'm not using slots by choice.  I'm using the standard
>>> lib "socket" class, which apparently uses slots.
>>
>> `socket` objects can't be pickled.  Not just because of the
>> `__slot__`\s but because a substantial part of their state lives in
>> the operating system's space.
> 
> Of course, if it makes sense to pickle sockets in the application, one
> is can do so by defining __getstate__ and __setstate__:

When does it make sense!?

> class Connection(object):
>     def __init__(self, host, port):
>         self.host = host
>         self.port = port
>         self.init_sock()
> 
>     def init_sock(self):
>         self.sock = socket.socket()
>         self.sock.connect((host, port))
>         ... init communication ...

But if you unpickle it while the original connection is still open it
can't connect.  If it's not open anymore, there's no one answering at
host/port anymore or some program that has no idea what this connection
is all about.

Ciao,
	Marc 'BlackJack' Rintsch