man/i3-dump-log: document -f (Thanks TonyC)

man/i3-dump-log.man

@@ -1,15 +1,15 @@
 i3-dump-log(1)
 ==============
-Michael Stapelberg <michael+i3@stapelberg.de>
-v4.1, December 2011
+Michael Stapelberg <michael@i3wm.org>
+v4.6, September 2013
 
 == NAME
 
 i3-dump-log - dumps the i3 SHM log
 
 == SYNOPSIS
 
-i3-dump-log [-s <socketpath>]
+i3-dump-log [-s <socketpath>] [-f]
 
 == DESCRIPTION
 
@@ -19,6 +19,9 @@ figuring out what is going on, without permanently logging to a file.
 
 With i3-dump-log, you can dump the SHM log to stdout.
 
+The -f flag works like tail -f, i.e. the process does not terminate after
+dumping the log, but prints new lines as they appear.
+
 == EXAMPLE
 
 i3-dump-log | gzip -9 > /tmp/i3-log.gz