Return_Values

   x                  Resultant value of the configuration attribute
                      specified in name.
   -1                 Indicates an error; errno is set to one of the
                      following values:

                      o  EACCES - Search permission is denied for a
                         component of the path prefix.

                      o  EINVAL - The name argument specifies an
                         unknown or inapplicable characteristic.

                      o  EFAULT - The path argument is an invalid
                         address.

                      o  ENAMETOOLONG - The length of the path
                         string exceeds PATH_MAX or a pathname
                         component is longer than NAME_MAX.

                      o  ENOENT - The named file does not exist
                         or the path argument points to an empty
                         string.

                      o  ENOTDI - A component of the path prefix is
                         not a directory.