Re: output streams vs output ports

[Shiro Kawai <shiro@xxxxxxxx>]

From: Taylor Campbell <campbell@xxxxxxxxxxxxxxxxxx>
Subject: Re: output streams vs output ports
Date: Sat, 18 Jun 2005 08:26:54 -0700 (PDT)

> But what benefit is achieved by having two identical (ignoring naming)
> layers for output, even if the separation from input streams & input
> ports is useful?

There could be an important difference between output streams and
output ports, w.r.t srfi-18 and srfi-21.  (BTW, this may be good to
be mentioned in this srfi as well).

Srfi-18 and srfi-21 require the conforming implementations to take
care of serializing simultaneous access to a port.  If we have
separate port/stream layers, the locking can be handled by the
port layer.  This frees up the stream layers from taking care
of expensive locking, which will be a performance gain for e.g.
translated streams.

--shiro