Any interest in swat enhancement

[Peter Samuelson]

[John E. Malmberg <wb8tyw at qsl.net>]
> I was assuming that one receiving pipe could accept messages from any
> number of sending pipes that could be temporarily opened to the
> receiving pipe while the message was being sent.

I think you are describing Unix domain sockets.  Plain old pipes have
very low overhead but are also very limited.  A pipe is half-duplex and
has a fixed-sized buffer (say 512 bytes).  It can be opened multiple
times for reading or writing, but if so it is a simple FIFO, i.e.,
multiple readers do NOT get multiple copies of the same data.  You can
use a single pipe as a message-passing conduit with many writers and
one reader, but then you must have an independent method (like a
message header) to identify each sender.  Andrew said N^2 because it's
simpler just to give each sender/receiver pair its own private pipe.

Peter