{
{   The purpose  of this request is to read the value of a variable or part of
{ a variable.  Only variables in the current block may be read.
{
{       CLP$READ_VARIABLE (REFERENCE, VARIABLE, STATUS)
{
{ REFERENCE: (input) This parameter specifies the variable or element or field
{       of  a variable to be read.  The parameter is given in the syntax of an
{       SCL variable reference except that if  a  subscript  is  part  of  the
{       reference  it  must  be  given  as  an  integer constant and not as an
{       expression.
{
{ VARIABLE: (output) This parameter specifies the variable or element or field
{       of the variable.
{
{ STATUS: (output) This parameter specifies the request status.
{       CONDITIONS: cle$improper_variable_reference, cle$unknown_variable.
{       IDENTIFIER: 'CL'
{
