| [/ |
| / Copyright (c) 2003-2010 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| / |
| / Distributed under the Boost Software License, Version 1.0. (See accompanying |
| / file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| /] |
| |
| [section:TimerService Timer service requirements] |
| |
| A timer service must meet the requirements for an [link |
| boost_asio.reference.IoObjectService I/O object service], as well as the |
| additional requirements listed below. |
| |
| In the table below, `X` denotes a timer service class for time type `Time` and |
| traits type `TimeTraits`, `a` denotes a value of type `X`, `b` denotes a value |
| of type `X::implementation_type`, `t` denotes a value of type `Time`, `d` |
| denotes a value of type `TimeTraits::duration_type`, `e` denotes a value of |
| type `error_code`, and `h` denotes a value meeting [link |
| boost_asio.reference.WaitHandler `WaitHandler`] requirements. |
| |
| [table TimerService requirements |
| [[expression] [return type] [assertion/note\npre/post-condition]] |
| [ |
| [`a.destroy(b);`] |
| [] |
| [ |
| From [link boost_asio.reference.IoObjectService IoObjectService] |
| requirements. Implicitly cancels asynchronous wait operations, as if by |
| calling `a.cancel(b, e)`. |
| ] |
| ] |
| [ |
| [`` |
| a.cancel(b, e); |
| ``] |
| [`size_t`] |
| [ |
| Causes any outstanding asynchronous wait operations to complete as soon |
| as possible. Handlers for cancelled operations shall be passed the error |
| code `error::operation_aborted`. Sets `e` to indicate success or failure. |
| Returns the number of operations that were cancelled. |
| ] |
| ] |
| [ |
| [`a.expires_at(b);`] |
| [`Time`] |
| [] |
| ] |
| [ |
| [`` |
| a.expires_at(b, t, e); |
| ``] |
| [`size_t`] |
| [ |
| Implicitly cancels asynchronous wait operations, as if by calling |
| `a.cancel(b, e)`. Returns the number of operations that were cancelled.\n |
| post: `a.expires_at(b) == t`. |
| ] |
| ] |
| [ |
| [`a.expires_from_now(b);`] |
| [`TimeTraits::duration_type`] |
| [ |
| Returns a value equivalent to `TimeTraits::subtract(a.expires_at(b), |
| TimeTraits::now())`. |
| ] |
| ] |
| [ |
| [`` |
| a.expires_from_now(b, d, e); |
| ``] |
| [`size_t`] |
| [ |
| Equivalent to `a.expires_at(b, TimeTraits::add(TimeTraits::now(), d), e)`. |
| ] |
| ] |
| [ |
| [`` |
| a.wait(b, e); |
| ``] |
| [`error_code`] |
| [ |
| Sets `e` to indicate success or failure. Returns `e`.\n |
| post: `!!e || !TimeTraits::lt(TimeTraits::now(), a.expires_at(b))`. |
| ] |
| ] |
| [ |
| [`` |
| a.async_wait(b, h); |
| ``] |
| [] |
| [ |
| Initiates an asynchronous wait operation that is performed via the |
| `io_service` object `a.io_service()` and behaves according to [link |
| boost_asio.reference.asynchronous_operations asynchronous operation] |
| requirements.\n |
| \n |
| The handler shall be posted for execution only if the condition |
| `!!ec || !TimeTraits::lt(TimeTraits::now(), a.expires_at(b))` |
| holds, where `ec` is the error code to be passed to the handler. |
| ] |
| ] |
| ] |
| |
| [endsect] |