In our project now we using log4cxx, but those library don't develope some years, also we have some problems with it. Could you advise some library for logging in C++. Library must support multithreade logging, system-log. Also it'll be good if it support logging via << operator. Also lib license must be very democracy - like boost, apache etc Crossplatform support. Must support linux, windows. Better if it support solaris, aix, hp-ux, but it's not necessary.