Fetch Environment variables in PL/SQL

How to get the value of environment variables in PL/SQL code
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1.For eBusiness Suite, you can also look at fnd_env_context table in your pl/sql code to get the path to the custom top variables as well.


2.A well coded program avoids hard-coding of paths and uses variables. If you want to get the value of unix environment variables in your programs, you can use the DBMS_SYSTEM.GET_ENV procedure. For applying it in E-Business Suite, you would need to make sure that the variables are defined in RDBMS $ORACLE_HOME/custom$CONTEXT_NAME.env

For example, I defined environment variable CUSTOM_TOP in a new file $ORACLE_HOME/custom$CONTEXT_NAME.env. This file is called automatically by your database environment file $CONTEXT_NAME.env.

To test, whether the value appears simply do this in an sql session:
SQL> set autoprint on
SQL> var CUSTOM_TOP varchar2(255)
SQL> exec dbms_system.get_env('CUSTOM_TOP',:CUSTOM_TOP);

PL/SQL procedure successfully completed.