Global Variables across sessions in PL/SQL package Specification

Question

Hi,
Is there a way I can share a variable value across sessions that doesnot affect by Commit/rollback.
The value would be set by one session and is visible across sessions, until it is set to another value by another/same session, and the new value is visible across.

Answer 1

V$Session is not granted to the user executing this. So, had to go with the context. Finally could resolve with the following code.
Run by DBA
create or replace context ctx1 using USER_procowner.pkg_global accessed globally;
grant execute on dbms_session to USER_procowner;
Run by user_procowner
create or replace package user_procowner.pkg_global AS
procedure set_lock(in_val IN VARCHAR2);
Function get_lock RETURN VARCHAR2;
end pkg_global;
create or replace package body user_procowner.pkg_global AS
procedure set_lock(in_val IN VARCHAR2) IS
begin
dbms_session.set_context('ctx1','var1',in_val);
end;
Function get_lock RETURN VARCHAR2 IS
begin
return (Sys_context('ctx1','var1'));
end;
end pkg_global;
grant execute on pkg_global to user_procuser;
exec user_procowner.pkg_global.set_lock('Y')
select user_procowner.pkg_global.get_lock Lock from dual;
LOCK
Y
exec user_procowner.pkg_global.set_lock('N')
select user_procowner.pkg_global.get_lock Lock from dual;
LOCK
N
The current value of var1 is visible across sessions using user_procowner.pkg_global.get_lock.
Thanks to all contributors.