If you kill -HUP or kill the spreadlogd process, it will not actually
process the signal until after it has received its next message from
Spread. You can move your log files to new names and then kill -HUP and
it will reopen the log files. This is useful for seamless log rotation
without losing any messages.

Spread is really cool. It is a poweful group communication toolkit
developed at the Center for Networking and Distributed Systems at the
Johns Hopkins University
(http://www.spread.org/ and http://www.cnds.jhu.edu/, respectively).

See also: http://www.lethargy.org/mod_log_spread/
