OSF DCE Application Development Guide--Introduction and Style Guide

Binding
the context handle. Also, the stub will not attempt to renew such a cached binding if the
client-server connection fails. Even if the server is still running and the connection
could be reestablished, the server will have rundown the context it is holding for the
client, so that the context handle will no longer be valid. When implicit binding is in
effect, a call made with a context handle and without an explicit binding parameter will
use the cached binding associated with the context handle rather than the implicit
binding.
The following table summarizes the binding semantics applied to a client operation:
TABLE 4-1. Binding Semantics
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ACF ACF ACF ACF/IDL IDL Binding
__________________________________________________________________________________________
__________________________________________________________________________________________
auto_handle implicit_handle explicit_handle explicit_handle context Semantics
attribute? attribute? attribute attribute handle?
on interface? on operation?
__________________________________________________________________________________________
No No No No No Auto
No No No No Yes Auto
(context handle)
No No No Yes No Explicit
No No No Yes Yes Explicit
__________________________________________________________________________________________
Yes No No No No Auto
Yes No No Yes No Explicit
Yes No No No Yes Auto
(context handle)
Yes No No Yes Yes Explicit
__________________________________________________________________________________________
No Yes No No No Implicit
No Yes No Yes No Explicit
No Yes No No Yes Auto (context handle)
No Yes No Yes Yes Explicit
__________________________________________________________________________________________
No No Yes No No Explicit
No No Yes Yes No Explicit
No No Yes No Yes Explicit
No No Yes Yes Yes Explicit
__________________________________________________________________________________________
When a binding handle is selected automatically by the client stub, there is no way for
the application to specify authentication data. In principle, it would be possible to have
the client authenticate itself to the server in such a case, although a client that does not
care about which server it calls obviously cannot authenticate the server. In practice,
calls made with automatic bindings are simply unauthenticated. Therefore, if your
application cares about authentication, it should avoid using automatic binding.
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