OSF DCE Application Development Guide--Introduction and Style Guide

OSF DCE Application Development Guide—Introduction and Style Guide
2. If cancelability state is deferred, then cancellation requests will be sent to the
server where they will be handled according to the server’s setting of the
cancelability state for the application thread extension (that is, the call thread) in
the server. If ignored at the server, the client side would then effect the cancel
upon return from the RPC, so the cancel would not be lost or incorrectly handled.
In particular, the timeslice interrupt (context switch) is a cancellation point in DCE
threads, so that even if a cancel were ignored by the server side, when the RPC
returns, the thread will be at a cancellation point.
3. If cancelability state is asynchronous, then cancellation can happen at any time.
In general, this state is not recommended across the scope of an RPC in line with
the rule that most routines that do useful work are not asynchronous cancel safe
and thus should not be called with asynchronous cancelability state.
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