Let syslog(3) use RFC 5424.

With r332099 changing syslogd(8) to parse RFC 5424 formatted syslog
messages, go ahead and also change the syslog(3) libc function to
generate them. Compared to RFC 3164, RFC 5424 has various advantages,
such as sub-second precision for log entry timestamps.

As this change could have adverse effects when not updating syslogd(8)
or using a different system logging daemon, add a notice to UPDATING and
increase __FreeBSD_version.

Differential Revision:	https://reviews.freebsd.org/D14926

1 files changed, 39 insertions, 0 deletions

diff --git a/UPDATING b/UPDATING
index 1eb37cb050cd6..aadef95258e45 100644
--- a/UPDATING
+++ b/UPDATING
@@ -51,6 +51,45 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 12.x IS SLOW:
 
 ****************************** SPECIAL WARNING: ******************************
 
+20180406:
+	In addition to supporting RFC 3164 formatted messages, the
+	syslogd(8) service is now capable of parsing RFC 5424 formatted
+	log messages. The main benefit of using RFC 5424 is that clients
+	may now send log messages with timestamps containing year numbers,
+	microseconds and time zone offsets.
+
+	Similarly, the syslog(3) C library function has been altered to
+	send RFC 5424 formatted messages to the local system logging
+	daemon. On systems using syslogd(8), this change should have no
+	negative impact, as long as syslogd(8) and the C library are
+	updated at the same time. On systems using a different system
+	logging daemon, it may be necessary to make configuration
+	adjustments, depending on the software used.
+
+	When using syslog-ng, add the 'syslog-protocol' flag to local
+	input sources to enable parsing of RFC 5424 formatted messages:
+
+		source src {
+			unix-dgram("/var/run/log" flags(syslog-protocol));
+		}
+
+	When using rsyslog, disable the 'SysSock.UseSpecialParser' option
+	of the 'imuxsock' module to let messages be processed by the
+	regular RFC 3164/5424 parsing pipeline:
+
+		module(load="imuxsock" SysSock.UseSpecialParser="off")
+
+	Do note that these changes only affect communication between local
+	applications and syslogd(8). The format that syslogd(8) uses to
+	store messages on disk or forward messages to other systems
+	remains unchanged. syslogd(8) still uses RFC 3164 for these
+	purposes. Options to customize this behaviour will be added in the
+	future. Utilities that process log files stored in /var/log are
+	thus expected to continue to function as before.
+
+	__FreeBSD_version has been incremented to 1200061 to denote this
+	change.
+
 20180328:
 	Support for token ring networks has been removed. If you
 	have "device token" in your kernel config you should remove