Struct Context::Id

This struct designates places in which a CPLEX generic callback can be invoked. The values defined here specify in which contexts CPLEX can invoke a callback. They are used in two different ways:

• They are used as arguments to the method IloCplex::Callback::Function::invoke to specify in which context the callback has just been invoked.
• A bit-wise OR of these values passes as an argument to the method IloCplex::use(Callback::Function, long) to specify in which places CPLEX should invoke the registered callback.

For details about the various context values, see the reference manual of the Callable Library (C API).

Important notes about the ThreadDown context:

• If a callback invoked in the ThreadUp context throws an exception, then ThreadDown will not be invoked on this thread.
• The callback function is not allowed to throw exceptions if invoked in the context ThreadDown. Any exception thrown in this context will be ignored.

Think of ThreadUp and ThreadDown as "constructor" and "destructor": the destructor is invoked only if the object was fully constructed and is not allowed to throw an exception.

See the documentation of CPX_CALLBACKCONTEXT_BRANCHING in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_CANDIDATE in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_GLOBAL_PROGRESS in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_LOCAL_PROGRESS in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_RELAXATION in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_THREAD_DOWN in the reference manual of the Callable Library (C API).

See the documentation of CPX_CALLBACKCONTEXT_THREAD_UP in the reference manual of the Callable Library (C API).