PL/SQL: get trace information

DBMS_OUTPUT.PUT_LINE('*** Error stack ***');
DBMS_OUTPUT.PUT_LINE(DBMS_UTILITY.FORMAT_ERROR_STACK);
DBMS_OUTPUT.PUT_LINE('*** Error backtrace ***');
DBMS_OUTPUT.PUT_LINE(DBMS_UTILITY.FORMAT_ERROR_BACKTRACE);
DBMS_OUTPUT.PUT_LINE('*** Call stack ***');
DBMS_OUTPUT.PUT_LINE(DBMS_UTILITY.FORMAT_CALL_STACK);