A module that interacts with the user usually defines a number of commands,
which can be invoked by the user from the command line. Commands can be bound
to a specific namespace (i.e., a class or an interface) or to the global
- Commands bound to classes are used to manipulate individual instances of
that class. For example, most devices have a status command that
prints the state of the device.
- Commands bound to interfaces can be used on all objects implementing that
interface. For example, the log-level command is available to all
objects implementing the log-object interface.
- Global commands can be used for things that do not pertain to a specific
object. This is the case of commands like output-radix or
For more information about writing new commands, refer to chapter 7.