If you are using the LOG4CXX_DEBUG and similar macros and some of the more
popular compilers, then you hopefully will get class and method information.
If you transliterated java code and are just doing "logger.debug("Msg"), then
that information is not available to you.
The performance issue mentioned in log4j isn't applicable to log4cxx. In
earlier version of log4j obtaining that information meant creating an
exception, printing its stack trace to a memory stream and then parsing that
stream to get the location. With the LOG4CXX_DEBUG macros, that information is
added to the generated logging call at compile time.
If you are able to see file and line, but not class and method, then explore
extending __LOG4CXX_FUNC__ to support your compiler.
On Oct 15, 2010, at 4:08 PM, Jacob L. Anawalt wrote:
> On 10/15/2010 5:53 AM, Thorsten Schöning wrote:
>> Hello,
>>
>> is there any way to get the method name of the logging caller in the
>> log message?
>
> As you say, the log4j docs document %M in the PatternLayout (while log4cxx
> does not) but caution against the inefficiency of it's use. Additionally "The
> Complete Log4J Manual" (a good document to have) points out that even in Java
> this information can be discarded by the compiler.
>
> In log4cxx %F and %L provide the file name and line number respectively, but
> that is because they can rely on the ubiquitious __FILE__ and __LINE__
> macros. The LOG4CXX_LOCATION macro is documented to use __LOG4CXX_FUNC__ with
> a value of "".
>
> If your compiler and flags support __FUNCTION__, you could work that into
> your message or change the definition of __LOG4CXX_FUNC__ and go on to
> implement %M.
>
> I haven't even glanced at the code to see where that's at. I just inflexibly
> typed the function name into a DEBUG message near the top of the message
> call, or sometimes used a NDC to track the call stack in debug logs.
>
> Good luck,
> --
> Jacob Anawalt
> Gecko Software, Inc.
> janaw...@geckosoftware.com
> 435-752-8026
