Which version are you using? $ sqlplus / SQL*Plus: Release 10.2.0.2.0 - Production on Mon Sep 18 20:46:13 2006 Copyright (c) 1982, 2005, Oracle. All Rights Reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production With the Partitioning, OLAP and Data Mining options SQL> alter system set "_trace_files_public"=true; alter system set "_trace_files_public"=true * ERROR at line 1: ORA-02095: specified initialization parameter cannot be modified SQL> alter system set "_trace_files_public"=true scope=spfile; System altered. SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production With the Partitioning, OLAP and Data Mining options $ stop_oracle Processing Database instance "10G": log file /oracle/product/10g/shutdown.log $ start_oracle Processing Database instance "10G": log file /oracle/product/10g/startup.log $ alter session set tracefile_identifier=DERYA; Session altered. SQL> alter session set events='10046 trace name context forever, level 12' SQL> / Session altered. SQL> select * from emp; EMPNO ENAME JOB MGR HIREDATE SAL COMM ---------- ---------- --------- ---------- --------- ---------- ---------- DEPTNO ---------- 7369 SMITH CLERK 7902 17-DEC-80 800 20 7499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 30 7521 WARD SALESMAN 7698 22-FEB-81 1250 500 30 7566 JONES MANAGER 7839 02-APR-81 2975 20 7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 30 7698 BLAKE MANAGER 7839 01-MAY-81 2850 30 7782 CLARK MANAGER 7839 09-JUN-81 2450 10 7788 SCOTT ANALYST 7566 19-APR-87 3000 20 7839 KING PRESIDENT 17-NOV-81 5000 10 7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30 7876 ADAMS CLERK 7788 23-MAY-87 1100 20 7900 JAMES CLERK 7698 03-DEC-81 950 30 7902 FORD ANALYST 7566 03-DEC-81 3000 20 7934 MILLER CLERK 7782 23-JAN-82 1300 10 14 rows selected. SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production With the Partitioning, OLAP and Data Mining options $ cd /oracle/product/10g/admin/oracle/udump/ $ ls 10g_ora_2919.trc 10g_ora_2790.trc 10g_ora_3315.trc 10g_ora_3126.trc 10g_ora_2946.trc 10g_ora_2823.trc 10g_ora_4252.trc 10g_ora_3153.trc 10g_ora_3195.trc 10g_ora_2832.trc 10g_ora_6286.trc 10g_ora_3301.trc 10g_ora_3044.trc 10g_ora_3173.trc 10g_ora_6330.trc 10g_ora_3436.trc 10g_ora_3072.trc 10g_ora_3224.trc 10g_ora_6593.trc 10g_ora_3463.trc 10g_ora_3274.trc 10g_ora_3227.trc 10g_ora_3114.trc 10g_ora_3464.trc 10g_ora_6356.trc 10g_ora_4956.trc 10g_ora_3141.trc 10g_ora_3554_DERYA.trc 10g_ora_6383.trc 10g_ora_3288.trc 10g_ora_3300.trc And, finally: $ ls -l 10g_ora_3554_DERYA.trc -rw-r--r-- 1 501 220525 Sep 18 20:50 10g_ora_3554_DERYA.trc As you can see, it's publicly readable. -- Mladen Gogala http://www.mgogala.com -- //www.freelists.org/webpage/oracle-l