Boost C++ Libraries: Ticket #12369: In boost::log, how to print extra header line when file rotation/rollover

status changed; resolution set

Andrey Semashev — Tue, 02 Aug 2016 15:49:30 GMT

status new → closed
resolution → invalid

See open/close handlers.

http://www.boost.org/doc/libs/1_61_0/libs/log/doc/html/log/detailed/sink_backends.html#log.detailed.sink_backends.text_file

anonymous — Tue, 02 Aug 2016 21:07:42 GMT

Replying to andysem:

See open/close handlers.

http://www.boost.org/doc/libs/1_61_0/libs/log/doc/html/log/detailed/sink_backends.html#log.detailed.sink_backends.text_file

Hi, The example in that link works fine for narrow char. I am using wide char header line. But I can not find the wide char version of text_file_backend::stream_type. Which one shall I use? Thank you.

Your example:

void write_header(sinks::text_file_backend::stream_type& file)
{
    file << "<?xml version=\"1.0\"?>\n<log>\n";
}
...
sink->locked_backend()->set_open_handler(&write_header);

Andrey Semashev — Tue, 02 Aug 2016 22:51:47 GMT

There is no wide character version as the sink backend already operates on converted characters. If you have national characters in your header/footer you'll have to perform character conversion yourself.