This is a very rudimentary portable interface to an underlying
operating system.
| app-filename | (=> <str>) | M | 
|  | returns the filename of the application. |  | 
| app-args | (=> <lst>) | M | 
|  | returns a list of argument strings with which the application 
       was called. |  | 
| os-name | (=> <str>) | M | 
|  | returns name of current operating-system. |  | 
| os-val | (s|<str> => <str>) | M | 
|  | returns OS environment variable value. |  | 
| os-val-setter | (v|<str> s|<str> => <str>) | M | 
|  | sets OS environment variable value. |  | 
| process-id | (=> <int>) | M | 
|  | returns the process id of the current GOO process. |  | 
|  |