[Twisted-Python] Named Pipes

Wari Wahab wari at home.wari.org
Sat May 17 00:45:45 EDT 2003

Moshe Zadka wrote:
>>Hi, is there a way to get twisted to listen to a named pipe like it's a 
>>TCP connection or something? How would I go about it?
> It's fairly easy, and probably should be done in Twisted at some point.

Ah, I got my own based on stdio.StandardIO and that does not work the 
way I want, this way seems better :)

> from twisted.internet import abstract, fdesc
> class SelectableFile(abstract.FileDescriptor):
>     def __init__(self, fp, protocol):
>         self.fp = fp
>         fdesc.setNonBlocking(fp)
>         self.protocol = protocol
>         self.protocol.makeConnection(self)
>         self.fileno = self.fp.fileno
>     def doRead(self):
>         buf = self.fp.read(4096)

I had to do this on a try block:
     buf = self.fp.read(4096)
except IOError:
     buf = None
>         if buf:
>             self.protocol.dataReceived(buf)
>         else:
>             self.protocol.connectionLost()
>     def write(self, data):
>         pass # what can we do with the data?
>     def loseConnection(self):
>         self.fp.close()

Wait, how did you guys make it so easy? :) Anyway, I find that 
loseConnection is never called (when I restart syslog, or when I deleted 
the named pipe), this thing goes on like a battery, of course the effect 
of deleting the file and recreating it does not get the communications 
working anymore because of inode/filepointer diffences.

Thanks for pointing this one out to me.

Regards: Wari Wahab
RoughingIT - http://roughingit.subtlehints.net
PyBlosxom  - http://roughingit.subtlehints.net/pyblosxom

More information about the Twisted-Python mailing list