C++ thread name map and log4cxx

Question

With std::thread, it is now trivial to keep a list of threads names in the program state (either by wrapping the thread, or by using a singleton to manage the thread list.)

I am starting to use log4cxx for my logging, and I'd like to have it display the thread name. However, this means I cannot use the PatternLayout. The thread numbers aren't very useful on their own.

What is the best way to do this? Am I stuck with just outputting a map, or can I override PatternLayout/ConversionPattern in a clever way to do what I want? And if I overload it, how do I point to the class in the config file? Or can I possibly add a conversion character?

score 1 · Accepted Answer · edited May 23 '17 at 12:11

Put your thread names using MDC before setting logger in your program

 MDC::put( "threadName", threadNameString);

Then at XML config

   <layout class="org.apache.log4j.PatternLayout">
      <param name="ConversionPattern" value="%X{threadName} "/>
    </layout>

So at each log message your thread name will apear.

For more info check answer of this question: Add process id to log file name in log4cxx

C++ thread name map and log4cxx

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