Accessing environment variables in PL/SQL??

Question

I have two oracle schemas; myenv1 and myenv2. They are both exact copies from each other except for the fact that one is my "developement" environment and the other my "production" environment.
So in each of them I have some packages with PL/SQL code.
I'd like to have an environment variable called PLATFORM (maybe not the best name) that should have the value "devel" in one schema and the value "prod" in the other schema. And I'd like to be able to access this variable in my PL/SQL code so I can slightly change some code or conditionate some code to the production environment only... or stuff like that.
Does anyone know how to do that? (where and how to configure the env. variable)
Any help will be most appreciated.
Thanks!

Answer 1

but I'm using the same 'current_user' in both schemas... is there other values I can get with sys_context ?? maybe there's one that would do it... but i think it's not 'current_user' It should be. Consider:
SQL> show user
USER is "SCOTT"
SQL> create or replace function show_user return varchar2
  2  as
  3  begin
  4    return sys_context('userenv','current_user');
  5  end show_user;
  6  /
Function created.
SQL> select show_user from dual;
SHOW_USER
SCOTT
SQL> grant execute on show_user to test;
Grant succeeded.
SQL> connect test/test
Connected.
SQL> select scott.show_user from dual;
SHOW_USER
SCOTT