suplib/src/ChannelMux.i3


 Copyright 1997-2003 John D. Polstra.
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 *      This product includes software developed by John D. Polstra.
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 * $Id: ChannelMux.i3.html,v 1.3 2010-04-29 17:20:02 wagner Exp $ 

INTERFACE ChannelMux;

IMPORT Atom, IP, Rd, Thread, Wr;
IMPORT ConnFD;

TYPE
  T <: ROOT;

  Channel <: ConnFD.T;

  ChannelID = [0..255];

VAR
Error atoms in addition to those defined in the IP and TCP interfaces.
  ProtocolError: Atom.T;

PROCEDURE Open(rd: Rd.T;
               wr: Wr.T;
	       VAR (*OUT*) chan: Channel;
	       active: BOOLEAN): T
  RAISES {IP.Error, Thread.Alerted};
Creates and initializes a new channel multiplexer communicating on top of the given reader/writer pair.

PROCEDURE Listen(mux: T): ChannelID
  RAISES {IP.Error};
Creates a new channel in the listening state, and returns its ID.

PROCEDURE Accept(mux: T; id: ChannelID): Channel
  RAISES {IP.Error, Thread.Alerted};
Waits for an incoming connection on the given channel.

PROCEDURE Connect(mux: T; id: ChannelID): Channel
  RAISES {IP.Error, Thread.Alerted};
Initiates a connection to the given channel.

PROCEDURE Close(mux: T);
Shuts down the packet multiplexer.

END ChannelMux.