[users@httpd] Apache 2.4.41 checking env variable value

[Salim Abdul -X (salimabd - HCL TECHNOLOGIES LIMITED at Cisco)]

Hi Experts,

I want to check the value of an environment variable which is already set.

<Directory />
    AllowOverride None
    Require env XYZ == 'SUCCESS' || expr "%{REQUEST_URI} == 
'/xyz/register/register.rq'"
</Directory>

Here I want to check the variable is 'SUCCESS'. What is the correct syntax to 
check the value of the env variable.

Thanks in advance,

Regards,
Salim