Task

Rename:

   a file called     input.txt     into     output.txt     and 
   a directory called     docs     into     mydocs.


This should be done twice:  
once "here", i.e. in the current working directory and once in the filesystem root.

It can be assumed that the user has the rights to do so.

(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)




OS.FileSys.rename {old = "input.txt", new = "output.txt"};
OS.FileSys.rename {old = "docs", new = "mydocs"};
OS.FileSys.rename {old = "/input.txt", new = "/output.txt"};
OS.FileSys.rename {old = "/docs", new = "/mydocs"};