Paper Details

%T XCHANs: Notes on a New Channel Type
%A Øyvind Teig
%E Peter H. Welch, Frederick R. M. Barnes, Kevin Chalmers, Jan Bækgaard Pedersen, Adam T. Sampson
%B Communicating Process Architectures 2012
%X This paper proposes a new channel type, XCHAN, for
   communicating messages between a sender and receiver.
   Sending on an XCHAN is asynchronous, with the sending
   process informed as to its success. XCHANs may be buffered,
   in which case a successful send means the message has got
   into the buffer. A successful send to an unbuffered XCHAN
   means the receiving process has the message. In either case,
   a failed send means the message has been discarded. If
   sending on an XCHAN fails, a built\-in feedback channel (the
   x\-channel, which has conventional channel semantics) will
   signal to the sender when the channel is ready for input
   (i.e., the next send will succeed). This x\-channel may be
   used in a select or ALT by the sender side (only
   input guards are needed), so that the sender may passively
   wait for this notification whilst servicing other events.
   When the x\-channel signal is taken, the sender should send
   as soon as possible \-\- but it is free to send something
   other than the message originally attempted (e.g.
   some freshly arrived data). The paper compares the use of
   XCHAN with the use of output guards in select/ALT
   statements. XCHAN usage should follow a design pattern,
   which is also described. Since the XCHAN never blocks, its
   use contributes towards deadlock\- avoidance. The XCHAN
   offers one solution to the problem of overflow handling
   associated with a fast producer and slow consumer in message
   passing systems. The claim is that availability of XCHANs
   for channel based systems gives the designer and programmer
   another means to simplify and increase quality.

If you have any comments on this database, including inaccuracies, requests to remove or add information, or suggestions for improvement, the WoTUG web team are happy to hear of them. We will do our best to resolve problems to everyone's satisfaction.

Copyright for the papers presented in this database normally resides with the authors; please contact them directly for more information. Addresses are normally presented in the full paper.