If your logging requirements are modest or you like to begin light, then clue may be for you. clue is a C++03 header-only library to log messages with a severity and optional module identifier. Provided logging destinations are the console, the Windows debugger, the Windows event log, an in-memory log (string) and Unix syslog. You can also define your own logging destination. clue is based on an idea by Mark Nelson, presented in DrDobbs  and on ideas found in the CATCH test framework by Phil Nash .