Nope, in the system we use, the tracing code isn't even called unless tracing is actually enabled (which can be done in realtime from other processes). The only overhead incurred for any logging statement currently not active is little more than a lookup, compare, and jump.
From the discussion I've seen, the proposed library should work the same way.
Yup, it does work the same way -- except that for my lib there's not even a lookup. Every log internally is a reference to a variable of boost::log::logger type, which contains a pointer to a boost::log::logger_impl, which contains a boolean variable. Best, John -- John Torjo, Contributing editor, C/C++ Users Journal -- "Win32 GUI Generics" -- generics & GUI do mix, after all -- http://www.torjo.com/win32gui/ -v1.6.3 (Resource Splitter) -- http://www.torjo.com/cb/ - Click, Build, Run!