
     _________________________________________________________________

  TAO's CORBA Object Services Directory Hierarchy

   The  file and directory organization for TAO services can be confusing
   at first glance (and even on subsequent ones to be honest), so we felt
   like  some  rationale  and  explanation of the directory hierarchy was
   needed.

   For   general   sanity  all  TAO  services  files  are  located  under
   $TAO_ROOT/orbsvcs.

   It is expected that clients use more than one service at the same time
   (in  fact  some  of  the  services  already do, for instance the Event
   Service  uses the Naming Service and the Scheduling Service). For this
   reason all the services stubs are grouped in one library. This library
   is  located  in $TAO_ROOT/orbsvcs/orbsvcs. Usually the include path is
   only $TAO_ROOT/orbsvcs, so files are included like this:

   #include "orbsvcs/CosNamingC.h"

   To  simplify the IDL generation the skeletons are also on the library,
   this  is  not  a problem for client programs and most services need to
   link  the library anyway (since they use other services.) Further, the
   current  support  for  collocation  requires  that  clients  link  the
   skeleton files anyway.

   In  the  future  we intend to use ACE Service Configurator to give the
   users  control  over  collocation of the services implementation. As a
   first  cut all the service implementations are included in the orbsvcs
   library  $TAO_ROOT/orbsvcs/orbsvcs.  Since there are serveral services
   and  each  one  is  implemented  using  several  files we have given a
   different  directory  to  each  service.  This  structure  could  also
   simplify   a  future  split  into  several  libraries  (if  it  proves
   necessary).

   The complete list of directories is:

            Service          Implementation Sub-directory
   A/V Streams Service       orbsvcs/AV
   Concurrency Service       orbsvcs/Concurrency
   Event Service             orbsvcs/CosEvent
   Real-time Event Service   orbsvcs/Event
   LifeCycle Service         orbsvcs/LifeCycle
   Load Balancing Service    orbsvcs/LoadBalancing
   Logging Service           orbsvcs/Log
   Naming Service            orbsvcs/Naming
   Property Service          orbsvcs/Property
   Scheduling Service        orbsvcs/Sched
   Security Service          orbsvcs/Security
   SSLIOP Pluggable Protocol orbsvcs/SSLIOP
   Trading Service           orbsvcs/Trader
   Time Service              orbsvcs/Time
   Notification Service      orbsvcs/Notify

   Note  that  in  the  current  version  of TAO we still have standalone
   binaries for some of the services. However, some applications may want
   to control what process implements a particular service. Therefore, it
   has  proved  useful  for  debugging  purposes  to  keep  the most used
   services   separated.   The   binaries  in  question  are  located  in
   $TAO_ROOT/orbsvcs, and the list includes:
     * Concurrenty_Service
     * Dump_Schedule
     * LifeCycle_Service
     * LoadBalancer
     * CosEvent_Service
     * Event_Service
     * Naming_Service
     * Scheduling_Service
     * Trading_Service
     * Time_Service
     * ImplRepo_Service *(see below)*
     * Notify_Service

   In  the  future  we  plan  to  use  a  single  binary  and ACE Service
   Configurator and keep a single binary.

   The  Implementation  Repository  is a unique service in that it starts
   server  executables,  and  it  doesn't  make  sense to collocate it in
   another  server.  Because  of  this, only the IDL files are located in
   $TAO_ROOT/orbsvcs/orbsvcs.   The   other  files  are  all  located  in
   $TAO_ROOT/orbsvcs/ImplRepo_Service.

   Finally    the   tests   and   example   programs   are   located   in
   $TAO_ROOT/orbsvcs/tests; once more each may involve more than a single
   binary,  so  each one is kept in its own directory; the following list
   describes the contents of each one:

   Test directory Purpose
   AVStreams A complete A/V server and client.
   Concurrency Test the Concurrency Service.
   CosEC_Basic  Test  the  basic  functionality  of  the  standard  Event
   Service.
   CosEC_Multiple  Simple example that connects multiple consumers and/or
   suppliers  to  the  standard event service. It can be used to show how
   composing  a  standard  event-service  and the real-time event service
   provides filtering capabilities.
   EC_Basic Test the basic functionality of the real-time Event Service.
   EC_Custom_Marshal  Show  how the Real-time event service can send user
   defined data using custom marshaling.
   EC_Mcast  Multiple  real-time  event  channels  can  communicate using
   multicast, this example shows how to do it.
   EC_Multiple Connect two Real-time Event Channels using the EC_Gateway,
   measure latency, utilization and minimum spacing.
   EC_Throughput Measure throughput and latency for collocated and remote
   real-time event services.
   Event_Latency  Test the Real-time Event Service and measure end-to-end
   latency, it also uses the Scheduling and Naming services.
   ImplRepo  Tests  used  to test the functionality of the Implementation
   Repository Service.
   LoadBalancing Test that exercises the Load Balancing service.
   Logger An example logging service using the Naming Service to locate a
   factory.
   Naming This is an obsolete directory.
   Property Testing for the Property Service.
   Sched A test of the Scheduling Service.
   Security  Tests  that  verify that the Security Service is functioning
   properly.  Tests for auxiliary Security Service components such as the
   SSLIOP pluggable protocol also exist in this directory.
   Simple_Naming  A  number  of Naming Service tests: from very simple to
   more fancy.
   Simulator  Prototype implementation of DOVE (DOVE Agent, DOVE Browser,
   DOVE  MIB,  DOVE  Application).  The  DOVE Agent consists of the Event
   Channel,  which  is  then  connected  to a DOVE Browser implemented in
   Java.
   Trading Tests for the Trading Service.
   Time A test for the Time Service.
   Notify  Consists  of basic tests foe the Notification Service - Simple
   event  transfer,  client Connect-Disconnect to event channel, creating
   and  destroying  channel/admin objects,test for Admin properties, test
   to   check   offer/subscription   changes.   The  directory  also  has
   performance tests for throughput.

SEE ALSO

   You  may  you to check TAO [1]release notes for up to date information
   on status, changes, future work, etc.
     _________________________________________________________________


    [2]Carlos O'Ryan

References

   1. file://localhost/tmp/ACE_wrappers_stage-29436/ACE_wrappers/TAO/docs/releasenotes/index.html
   2. mailto:coryan@macarena.cs.wustl.edu
