Creating a logging library and have questions

[sybrandy]

>
> I second Rainer. A logging system should commit (at least) error messages immediately, particularly if the application has multiple threads. Otherwise it is going to make debugging a crashing system a nightmare.  When I do it I just stick 'synchronized' in front of the statement that does the write.
>
>

Yes, I fully understand that and in the current single-threaded version 
I have, that's exactly what happens: all error and fatal messages cause 
the buffer to flush.

What I'm looking for is the best way to handle having a daemon writer. 
My biggest concern here is multi-threaded applications.  Granted, it 
would be nice to not have the writing in the same thread as the rest of 
the code to try to keep file I/O from affecting performance, but that's 
secondary.

Here's what I know: a variable of type OutputStream cannot be shared.  I 
did not try using __gshared, but regardless while this would work and I 
could easily synchronize the writes, I can see a lot of contention if 
multiple threads trying to write a lot of data to a log file. (E.g. 
trace statements that capture variable states to enhance debugging) 
Granted, this shouldn't be the case in production code, but if I can 
find a better way to do this, I'd love to.  This is why I thought that 
the new threading model with message passing would be good, but I again 
have concerns if there are a lot of messages trying to be written.  I 
know in Erlang you can fill up the message buffer if you're not careful.

Casey