SQL> CREATE OR REPLACE PROCEDURE p
...

SQL> select * from v$version where rownum =  1 ;

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Oracle9i Enterprise Edition Release  9 . 2 . 0 . 6 . 0  - Production

SQL> CREATE OR REPLACE PROCEDURE ppp IS
   2   BEGIN
   3     dbms_output.put_line($$PLSQL_UNIT || ':' || TO_CHAR($$PLSQL_LINE));
   4   END;
   5   /

Warning: Procedure created with compilation errors.

SQL> show errors
Errors for PROCEDURE PPP:

LINE/COL ERROR
-------- -----------------------------------------------------------------
 3 / 24      PLS- 00103 : Encountered the symbol "$" when expecting one of the
         following:
         ( ) - + case mod new not null others <an identifier>
         <a double-quoted delimited-identifier> <a bind variable>
         table avg count current exists max min prior sql stddev sum
         variance execute multiset the both leading trailing forall
         merge year month DAY_ hour minute second timezone_hour
         timezone_minute timezone_region timezone_abbr time timestamp
         interval date
         <a string literal with character set specification>

SQL> create or replace procedure P is
   2   begin
   3     dbms_output.put_line($$PLSQL_UNIT || ':' || to_char($$PLSQL_LINE));
   4   end;
   5   /

Procedure created.

SQL> exec P
P: 3 

PL/SQL procedure successfully completed.

SQL> select * from v$version where rownum =  1 ;

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Oracle Database 10g Enterprise Edition Release  10 . 1 . 0 . 4 . 0  - Prod

SQL>