Return a UNIX FS type string of the current working 'directory'.

def cwd(self):
            """
            Return a UNIX FS type string of the current working 'directory'.
            """
            l_cwd                       = self.l_cwd[:]
            str_cwd                     = '/'.join(l_cwd)
            if len(str_cwd)>1: str_cwd  = str_cwd[1:]
            return str_cwd