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### asio_handler_allocate

Default allocation function for handlers.

    void * asio_handler_allocate(
        std::size_t size,
        ... );

Asynchronous operations may need to allocate temporary objects. Since asynchronous operations have a handler function object, these temporary objects can be said to be associated with the handler.

Implement asio_handler_allocate and asio_handler_deallocate for your own handlers to provide custom allocation for these temporary objects.

The default implementation of these allocation hooks uses `operator new` and `operator delete`.

##### Remarks

All temporary objects associated with a handler will be deallocated before the upcall to the handler is performed. This allows the same memory to be reused for a subsequent asynchronous operation initiated by the handler.

##### Example

    class my_handler;

    void* asio_handler_allocate(std::size_t size, my_handler* context)
    {
      return ::operator new(size);
    }

    void asio_handler_deallocate(void* pointer, std::size_t size,
        my_handler* context)
    {
      ::operator delete(pointer);
    }

##### Requirements

Header: `boost/asio/handler_alloc_hook.hpp`

Convenience header: `boost/asio.hpp`