LoggerFile( const fs::path &filePath = fs::path(), bool appendToExisting = true );
filePath defines the target logfile. For example, /tmp/cinder.log. If this parameter is left blank, LoggerFile will target a file named cinder.log that will sit next to the application binary.appendToExisting configures file appending. This parameter defaults to true.
LoggerFileRotating( const fs::path &folder, const std::string &formatStr, bool appendToExisting = true );
folder defines the root folder that will contain the logfile. If a blank string is provided, the folder will default to the folder that contains the application binary.formatStr is the string that will be evaluated by strftime and turned into the logfile name. For example, the string cinder.%Y.%m.%d.log could evaluate to cinder.2015.08.28.log. Note that, since the log name is only re-evaluated once daily, using a format that includes minutes or seconds may not produce the results you're expecting. If a blank format string is provided, an assertion will be thrown.appendToExisting configures file appending. This parameter defaults to true.