Procedure call from SQL*Plus in Korn Shell Script

Question

I am trying to excute a procedure from sqlplus, truncate_audit_table. I doesn't execute. If I do it manually
it executes. I have tried multiple ways, as below. This is inside a Korn Shell scripts that creates the procedure
and counts the aud$ table. All that works, but does not truncate the aud$ table. It does not do it, no error, just
passes it by. Does anybody know why?
${ORACLE_HOME}/bin/sqlplus -s / << EOF | tee -a ${LOG}
set feedback on
@/backup/oracle/orcl/audit/truncate_audit_table.sql
select count(*) from sys.aud$;
exec truncate_audit_table;
exit
EOF
${ORACLE_HOME}/bin/sqlplus -s / << EOF | tee -a ${LOG}
set feedback on
@/backup/oracle/orcl/audit/truncate_audit_table.sql
select count(*) from sys.aud$;
begin
     truncate_audit_table;
end;     
exit
EOF
This is the procedure that is being called:
create or replace procedure truncate_audit_table
as
begin
execute immediate 'truncate table sys.aud$';
end;
/

Answer 1

aud$ is owned by sys. You can see it does the count with or without the "\".
It creates the procedure under SYS , but does not execute it.
Truncate aud$ table...
Procedure created.
COUNT(*)
422
1 row selected.
===============================================================
audit_maintenance.ksh Completed: Thu Oct 26 14:03:17 GMT 2006
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