Reading through the doc for Boost.Log, it explains how to “fan out” into multiple files/sinks pretty well from one application, and how to get multiple threads working together to log to one place, but is there any documentation on how to get multiple processes logging to a single log file?
What I imagine is that every process would log to its own “private” log file, but in addition, any messages above a certain severity would also go to a “common” log file. Is this possible with Boost.Log? Is there some configuration of the sinks that makes this easy?
I understand that I will likely have the same “timestamp out of order” problem described in the FAQ here, but that’s OK, as long as the timestamps are correct I can work with that. This is all on one machine, so no remote filesystem problems either.
My expectation is that the Boost.Log backends that directly write logfiles will keep those files open in between writing the log entries.
This will cause problems with using the same logfile from multiple processes, because the filesystem usually won’t allow more than one process to write to a file.
There are a few Boost.Log backends that can be used to have all the logging end up in one place.
These are the syslog and Windows eventlog backends. Of these, the syslog backend is probably the easiest to use.