Rajpal Dangi wrote:
Rephrasing my second question from previous post. Suppose NORMAL, ERROR and CRITICAL severity logs are directed to text file. How to identify which one of them belong to ERROR severity?
I understand this can be done by using attribute (Tags in example) but I'm looking something implicit. So that we can avoid call to BOOST_LOG_SCOPED_LOGGER_TAG for each BOOST_LOG_SEV call.
What I meant by print severity in log file is to have severity level as part of log file contents i.e. For BOOST_LOG_SEV(my_crit_logger, NORMAL) << "This record is explicitly marked as to NORMAL";
Log file contents: ......[NORMAL] This record is explicitly marked as to NORMAL
Oh, I think, I understand now. What you need is to specify a formatter. Formatters are used to describe how different attributes will be represented in the log file. Severity level is one of the attributes, it is automatically registered by the severity_logger, so you don't need to put BOOST_LOG_SCOPED_LOGGER_TAG macros or anything around your log records. All you need is to define the formatter for the attribute and pass it to the sink backend. For example: // Assume, you have constructed the backend shared_ptr< text_ostream_backend > backend; // The formatter can be set in one of the two ways: // the lambda-like expression backend->set_formatter( ostrm << "[" << attr< int >("Severity") << "] " << message() ); // ... or with Boost.Format-like expression backend->set_formatter( format("[%1%] %2%") % attr< int >("Severity") % message() ); The "Severity" in these examples is the attribute name. It is the name that severity_logger uses to register the severity level attribute. int is the type of the attribute, it is currently predefined and cannot be customized. Now, you can log like this: enum level { NORMAL, ERROR, CRITICAL }; severity_logger lg; BOOST_LOG_SEV(lg, NORMAL) << "This record is explicitly marked as NORMAL"; BOOST_LOG_SEV(lg, Critical) << "This record is explicitly marked as CRITICAL"; The log file will contain then: [0] This record is explicitly marked as NORMAL [2] This record is explicitly marked as CRITICAL