This new patch replaces the previous one and addresses some of the 
concerns below....

Frank Ch. Eigler wrote:

>Hi -
>
>  
>
>>The attached patch adds logging support for sid components in 3 stages:
>>[...]
>>    
>>
>
>Looks fine - good use of virtual inheritance.  A few minor things
>I might have done differently:
>
>- make a new component type for named file I/O, instead of
>  changing sid-io-stdio; after all, stdio is bidirectional,
>  meant to be interactive
>
New component: sid-io-fileio

>- think of some other way to call stdout than "*"
>
Used "-" as originally intended and suggested by bje

>- make logging output buffering dependent on an attribute (set as the last
>  gasp of configuration) instead of pin-connectedness
>
Done

>- having a C++ flavour API (instead of printf()) for the logging function
>
A project for someone's copious spare time.

OK to commit?

Dave