{
{   This request creates an SCL "environment" variable.
{
{       CLP$CREATE_ENVIRONMENT_VARIABLE (NAME, SCOPE, ACCESS_MODE,
{         EVALUATION_METHOD, TYPE_SPECIFICATION, INITIAL_VALUE, STATUS)
{
{ NAME: (input)  This parameter specifies the name of the variable to be
{       created.
{
{ SCOPE: (input)  This parameter specifies the scope (residence) of the
{       environment variable.  The options are:
{
{       clc$environment_scope:  the variable is to be created in the current
{             block
{
{       clc$utility_scope:  the variable is to be created in the most recently
{             activated utility block
{
{       clc$task_scope:  the variable is to be created in the most recently
{             activated task block
{
{       clc$job_scope:  the variable is to be created in the job block
{
{       clc$push_scope:  this is, strictly speaking, not a true scope.  It is
{             provided as a convenience for defining environment variables in
{             a context where a definition may or may not have already been
{             made.
{
{             If the variable has already been defined as an environment
{             variable, it is PUSHed (see the clp$push_environment request for
{             information on pushing an environemnt variable).  The type must
{             be identical to the original definition.  If an initial value is
{             specified, it becomes the value of the PUSHed instance of the
{             variable.
{
{             If the variable has not already been defined, it is defined with
{             a scope of clc$environment_scope.
{
{ ACCESS_MODE: (input)  This parameter specifies how the variable, once
{       created, may be accessed.
{
{ EVALUATION_METHOD: (input)  This parameter specifies whether values assigned
{       to the variable are to be evaluated at the time of the assignment
{       (clc$immediate_evaluation) or at the time the variable is referenced
{       (clc$deferred_evaluation).  Immediate evaluation is the normal choice.
{
{ TYPE_SPECIFICATION: (input)  This parameter specifies the type of the
{       variable to be created.
{
{ INITIAL_VALUE: (input)  This parameter specifies the initial value to to be
{       given to the created variable.  If clc$read_write is specified for
{       ACCESS_MODE, no initial value need be supplied (indicated by giving a
{       NIL pointer).  If clc$read_only is specified, an initial value for the
{       variable must be supplied.
{
{ STATUS: (output) This parameter specifies the request status.
{
