boost.log當應用程序崩潰時，不存儲auto_flush文件

Question

最近，我開始玩boost.log，並遇到了一個問題，即如果拋出未引發異常，則不會將日誌消息寫入日誌文件。我正在使用滾動文本文件並設置了自動閃光選項。

這裏是從樣品中經修改的源：

#include <stdexcept> 
#include <string> 
#include <iostream> 
#include <fstream> 
#include <functional> 
#include <boost/ref.hpp> 
#include <boost/bind.hpp> 
#include <boost/shared_ptr.hpp> 
#include <boost/date_time/gregorian/gregorian.hpp> 
#include <boost/date_time/posix_time/posix_time_types.hpp> 
#include <boost/thread/thread.hpp> 
#include <boost/thread/barrier.hpp> 

#include <boost/log/common.hpp> 
#include <boost/log/filters.hpp> 
#include <boost/log/formatters.hpp> 
#include <boost/log/attributes.hpp> 
#include <boost/log/sinks.hpp> 
#include <boost/log/utility/empty_deleter.hpp> 
#include <boost/log/utility/record_ordering.hpp> 

namespace logging = boost::log; 
namespace attrs = boost::log::attributes; 
namespace src = boost::log::sources; 
namespace sinks = boost::log::sinks; 
namespace fmt = boost::log::formatters; 
namespace keywords = boost::log::keywords; 

using boost::shared_ptr; 
using namespace boost::gregorian; 

enum 
{ 
    LOG_RECORDS_TO_WRITE = 100, 
    LOG_RECORDS_TO_WRITE_BEFORE_EXCEPTION = 10, 
    THREAD_COUNT = 10 

}; 

BOOST_LOG_DECLARE_GLOBAL_LOGGER(test_lg, src::logger_mt) 

//! This function is executed in multiple threads 
void thread_fun(boost::barrier& bar) 
{ 
    // Wait until all threads are created 
    bar.wait(); 

    // Here we go. First, identify the thread. 
    BOOST_LOG_SCOPED_THREAD_TAG("ThreadID", boost::thread::id, boost::this_thread::get_id()); 

    // Now, do some logging 
    for (unsigned int i = 0; i < LOG_RECORDS_TO_WRITE; ++i) 
    { 
     BOOST_LOG(get_test_lg()) << "Log record " << i; 

     if(i > LOG_RECORDS_TO_WRITE_BEFORE_EXCEPTION) 
     { 
      BOOST_THROW_EXCEPTION(std::exception("unhandled exception")); 
     } 
    } 

} 

int main(int argc, char* argv[]) 
{ 
    try 
    { 
     typedef sinks::synchronous_sink<sinks::text_file_backend> file_sink; 
     shared_ptr<file_sink> sink(new file_sink(
      keywords::file_name = L"%Y%m%d_%H%M%S_%5N.log",  // file name pattern 
      keywords::rotation_size = 10 * 1024 * 1024,   // rotation size, in characters 
      keywords::auto_flush = true       // make each log record flushed to the file 
      )); 

     // Set up where the rotated files will be stored 
     sink->locked_backend()->set_file_collector(sinks::file::make_collector(
      keywords::target = "log"    // where to store rotated files 
      )); 

     // Upon restart, scan the target directory for files matching the file_name pattern 
     sink->locked_backend()->scan_for_files(); 

     sink->locked_backend()->set_formatter(
      fmt::format("%1%: [%2%] [%3%] - %4%") 
      % fmt::attr< unsigned int >("Line #") 
      % fmt::date_time<boost::posix_time::ptime>("TimeStamp") 
      % fmt::attr<boost::thread::id>("ThreadID") 
      % fmt::message() 
      ); 

     // Add it to the core 
     logging::core::get()->add_sink(sink); 

     // Add some attributes too 
     shared_ptr<logging::attribute> attr(new attrs::local_clock); 
     logging::core::get()->add_global_attribute("TimeStamp", attr); 
     attr.reset(new attrs::counter< unsigned int >); 
     logging::core::get()->add_global_attribute("Line #", attr); 

     // Create logging threads 
     boost::barrier bar(THREAD_COUNT); 
     boost::thread_group threads; 
     for (unsigned int i = 0; i < THREAD_COUNT; ++i) 
      threads.create_thread(boost::bind(&thread_fun, boost::ref(bar))); 

     // Wait until all action ends 
     threads.join_all(); 

     return 0; 
    } 
    catch (std::exception& e) 
    { 
     std::cout << "FAILURE: " << e.what() << std::endl; 
     return 1; 
    } 
} 

源是Visual Studio中下編譯爲升壓1.40 2008 boost.log編譯。

任何幫助，高度讚賞。

Answer 1

檢查日誌文件是否在進程的當前工作目錄中，而不是指定的文件收集器目標目錄（示例代碼中的「日誌」）。另外，您可能需要爲接收器「file_name」模式指定一個目錄。

正如「JQ」所指出的，不要期望看到任何日誌記錄後異常。