Read .aud files

Hi All

I have enabled database auditing to the filesystem.  My requirements are the following:

. To provide file logs of:
1. DB login with time; source machine;
2. DDL changes
3. SYS activity
4. Failed logins

So I turned on auditing like this:

ALTER SYSTEM SET audit_trail=OS SCOPE=SPFILE;

alter system set audit_file_dest='/oraaudit01/' scope=spfile;

alter system set audit_sys_operations=true scope=spfile;

audit alter any table by access;

audit create any table by access;

audit drop any table by access;

audit Create any procedure by access;

audit Drop any procedure by access;

audit Alter any procedure by access;