Without the optional parameter, displays the current history. Optional
argument 'n' specifies the number of commands that are kept in the
history list.
Note
To find out how the history mechanism works, please refer to
Section 3.2.
Example 4-8. history
>> history
1: base 4711 0x4711 04711 0b1000
2: help
3: ? h
>> h 2
>> h
2: help
3: ? h