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Subject: [Boost-users] Newby help with Boost::Log
From: Davies, John (john.davies_at_[hidden])
Date: 2018-11-08 13:50:24

I'm using Boost Log to capture all keypresses in my embedded device. I want to be able to store at most 3 files of a certain size and rotate them. That's working.

My problem is a scenario like this:
The device is inserting data into Log_009.log which is in the base folder. In the log folder are Log_006.log, Log_007.log, and Log_008.log.
The program stops and restarts. This may be due to some keypress that was logged in Log_009.log.
When it restarts, it clears out Log_009.log and starts it over - losing the last logged keypresses

Ideally, I'd like Boost Log to just keep appending to Log_009.log, but my reading online says that this isn't possible. My second favorite solution would be that Log_009 gets rotated and Log_010.log is started. Anything so I don't lose data.

Here is my configuration:

              keywords::file_name = "KeyLog_%3N.log",
              keywords::target = "./Logs",
              keywords::rotation_size = 500, // 10 * 1024 * 1024,
              keywords::format = "[%TimeStamp%]: %Message%",
              keywords::auto_flush = true,
              keywords::min_free_space = 30 * 1024 * 1024,
              boost::log::keywords::max_size = 20 * 1024,
              keywords::enable_final_rotation = true,
              keywords::scan_method = sinks::file::scan_matching,
              keywords::max_files = 3

Can you see what I'm missing? If a program exits via a crash, does final rotation occur? Maybe I need something like enable_initial_rotation.

Thanks for the help,

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