NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part2/17047

Internet Message Format | 1996-08-05 | 1.6 KB

Path: ix.netcom.com!news
From: [e-mail](Chris Lahey )
Newsgroups: comp.lang.c++
Subject: how to redirect ostream output
Date: 12 Apr 1996 22:13:20 GMT
Organization: Netcom
Message-ID: <4kmki0$[e-mail]>
NNTP-Posting-Host: dgr-il3-23.ix.netcom.com
X-NETCOM-Date: Fri Apr 12  5:13:20 PM CDT 1996

I am using a vendor's logging class that allows me to log to any
ostream I pass to it or by default it will log to stderr.  Rather than
write to a specific file or output device, I would like to be able to
recognize when a the string ends (by looking for a '\n') and then flush
the buffer to a queue using a package we purchased.

We are having trouble finding exactly where we need to put this logic.
The ostream class does not have any virtual methods, so we thought that
we should inherit from streambuf, since ostream's constructor is passed
a streambuf.  We weren't sure where to put our logic, so we overrode
all of streambuf's virtual functions with a single cout << "I'm here"
statement and then called the underlying streambuf function.
Unfortunately we found that (at least in our implementation on AIX
4.1.x) none of the virtual functions were being called.  So my question
is:

Where can we put this logic that will recognize when a '\n' is written
to the ostream so we can flush the current buffer to our queue using
the queue API's?  If it is not by inheriting from ostream or streambuf,
is there another class that we could inherit from to get the same
results.

Any help would be appreciated.

Thanks in advance,

Chris Lahey
CCC Information Services
Chicago
[e-mail]