several readers can attend the events from one or several containers.
The syntax of the command has been enhanced to interpret regular expressions.
If you want to monitor foo, lxc-monitor -n foo is the right command. If you
want to monitor foo and bar, you should specify lxc-monitor -n "foo|bar",
if you want to monitor all containers with the name beginning with 'foo',
you have to specify lxc-monitor -n "foo.*". More complex regexp can be specified
in accordance with the POSIX definitions, man regex (7).