System Log Functions
System Log functions are used when you must be certain that a log
entry will be written, even if the current transaction rolls back.
These kinds of logs are intended for use in debugging or tracking
invisible processes, such as a Paypal IPN transaction.
A log can be opened with SysLogOpen, which returns a handle to
the log. Log entries are made with SysLogEntry and the log is
eventually closed with SysLogClose.
The logs are stored in tables syslogs and syslogs_e.
The guarantee that the log entry will always be written comes at the
price of a separate connection to the database for each log. In a
debugging situation you can open as many of them as you need, but in
a production system they should only be used in highest need.