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io_service::run (1 of 2 overloads)

Run the io_service object's event processing loop.

std::size_t run();

The run() function blocks until all work has finished and there are no more handlers to be dispatched, or until the io_service has been stopped.

Multiple threads may call the run() function to set up a pool of threads from which the io_service may execute handlers. All threads that are waiting in the pool are equivalent and the io_service may choose any one of them to invoke a handler.

A normal exit from the run() function implies that the io_service object is stopped (the stopped() function returns true). Subsequent calls to run(), run_one(), poll() or poll_one() will return immediately unless there is a prior call to reset().

Return Value

The number of handlers that were executed.



Thrown on failure.


The run() function must not be called from a thread that is currently calling one of run(), run_one(), poll() or poll_one() on the same io_service object.

The poll() function may also be used to dispatch ready handlers, but without blocking.