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I recently tried to add some Boost log entries to a small application. However, using the log rotation, I somehow can't get it to pick up the correct counter in the logs directory.
For example, if my directory Logs
contains files Log_000.log
and Log_001.log
, I expect logging to start at Log_002.log
, but it always starts at 0.
I probably missed something, but if anyone can notice something, I would be grateful. Here's my startup code:
void initLogging()
{
boost::log::add_common_attributes();
auto core = boost::log::core::get();
core->add_global_attribute("UTCTimeStamp",boost::log::attributes::utc_clock());
auto x = boost::log::add_file_log(
boost::log::keywords::file_name = "Log_%3N.log",
boost::log::keywords::rotation_size = 2 * 1024, // 2k
boost::log::keywords::target = "Logs",
boost::log::keywords::min_free_space = 30 * 1024 * 1024,
boost::log::keywords::max_size = 20 * 1024, // 20k
boost::log::keywords::time_based_rotation = boost::log::sinks::file::rotation_at_time_point(boost::gregorian::greg_day(31)),
boost::log::keywords::scan_method = boost::log::sinks::file::scan_matching,
boost::log::keywords::format = "%UTCTimeStamp% (%TimeStamp%) [%ThreadID%]: %Message%",
boost::log::keywords::auto_flush = true
);
auto d = x->locked_backend()->scan_for_files();
}
Many thanks
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Aha! It looks like if you are using a helper add_file_log
it automatically calls scan_for_files
.
When called again, the counter looks like reset, so I just removed my call scan_for_files
Just pulled it out as an answer if he drove someone else insane!
Here's a working sample
You will see that after running 10 times it Logs/
contains:
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_080.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_081.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_082.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_083.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_084.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_085.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_086.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_087.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_088.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_089.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_090.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_091.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_092.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_093.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_094.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_095.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_096.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_097.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_098.log
-rw-r--r-- 1 2001 2000 998 Jul 17 16:26 Log_099.log
Code Listing
#define BOOST_LOG_DYN_LINK 1
#include <boost/log/core.hpp>
#include <boost/log/common.hpp>
#include <boost/log/attributes.hpp>
#include <boost/log/sinks.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <string>
void initLogging()
{
boost::log::add_common_attributes();
auto core = boost::log::core::get();
core->add_global_attribute("UTCTimeStamp",boost::log::attributes::utc_clock());
auto x = boost::log::add_file_log(
boost::log::keywords::file_name = "Log_%3N.log",
boost::log::keywords::rotation_size = 1 * 1024, // 1k
boost::log::keywords::target = "Logs",
boost::log::keywords::min_free_space = 30 * 1024 * 1024,
boost::log::keywords::max_size = 20 * 1024,
boost::log::keywords::time_based_rotation = boost::log::sinks::file::rotation_at_time_point(boost::gregorian::greg_day(31)),
boost::log::keywords::scan_method = boost::log::sinks::file::scan_matching,
boost::log::keywords::format = "%UTCTimeStamp% (%TimeStamp%) [%ThreadID%]: %Message%",
boost::log::keywords::auto_flush = true
);
//auto d = x->locked_backend()->scan_for_files();
}
int main()
{
initLogging();
for (int i = 0; i < 20; ++i) {
BOOST_LOG_TRIVIAL(trace) << "Let go shopping " << std::string(400, '*');
}
}
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