CosmOS
> Say it worked
it says: it worked
> Status
the last program left 0, which is: it did what it was asked
> Type
type: give me a file name
> Status
the last program left 2, which is: it was asked wrongly
> Type /nothing/here.txt
type: cannot find the file, error 2
> Status
the last program left 1, which is: it did not
> exit
halted
Execution halted.
[exit 0]