The libumberlog library serves two purposes: it's either a drop-in
replacement for the syslog() system call, in which case it turns the default
syslog messages into CEE-enhanced messages, with a CEE-JSON payload, and
some automatically discovered fields. Or, it can be used as a stand-alone
library, that provides a syslog()-like API, with the ability to add
arbitrary key-value pairs to the resulting JSON payload.

WWW: http://algernon.github.com/libumberlog/