Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!odi!benson
From: benson@odi.com (Benson I. Margulies)
Newsgroups: comp.lang.c++
Subject: Newline hook needed in streams
Message-ID: <1989Dec18.132745.5187@odi.com>
Date: 18 Dec 89 13:27:45 GMT
Reply-To: benson@odi.com (Benson I. Margulies)
Organization: Object Design Inc., Burlington, MA
Lines: 18

I've needed to implement two special kinds of ostreams that seem to
need "line buffering" support. That is, I need to have code of mine
get control (via virtual function or function pointer) whenever
a newline is inserted into the buffer.

The two examples are an indenting stream (add a settable amount
of indentation to the left margin) and a syslog stream.
The indenting stream needs to know newline boundaries to know
when to insert the indentation. The syslog stream wants to
actually call syslog(3) for each line of output.

Perhaps the next release of c++ could enhance the base classes
(ios and streambuf) to have line buffering in addition to 
just plain buffering and non-buffering.


-- 
Benson I. Margulies