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.)




  var  
    f : file ; // Untyped file
 begin
 
  // as current directory
  AssignFile(f,'input.doc');
  Rename(f,'output.doc');
 
  // as root directory
  AssignFile(f,'\input.doc');
  Rename(f,'\output.doc');
 
  // rename a directory 
  AssignFile(f,'docs');
  Rename(f,'mydocs');
 
  //rename a directory off the root
 
  AssignFile(f,'\docs');
  Rename(f,'\mydocs');
 
end;