--- /dev/null
+#! ./tesh
+
+$ $SG_TEST_EXENV ${bindir:=.}/log_usage "--log=root.fmt:[%10.6r]%e[%i:%P@%h]%e%m%n"
+> [ 0.000000] [0:@] Test with the settings ''
+> [ 0.000000] [0:@] val=2
+> [ 0.000000] [0:@] false alarm!
+> [ 0.000000] [0:@] Test with the settings ' '
+> [ 0.000000] [0:@] val=2
+> [ 0.000000] [0:@] false alarm!
+> [ 0.000000] [0:@] Test with the settings ' test.thres:info root.thres:info '
+> [ 0.000000] [0:@] val=2
+> [ 0.000000] [0:@] false alarm!
+> [ 0.000000] [0:@] Test with the settings ' test.thres:verbose root.thres:error '
+> [ 0.000000] [0:@] val=2
+> [ 0.000000] [0:@] false alarm!
+> [ 0.000000] [0:@] Test with the settings ' test.thres:critical '
+> [ 0.000000] [0:@] false alarm!