| [/ |
| / Copyright (c) 2003-2021 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:SignalHandler Signal handler requirements] |
| |
| A signal handler must meet the requirements for a [link |
| asio.reference.Handler handler]. A value `h` of a signal handler class |
| should work correctly in the expression `h(ec, n)`, where `ec` is an lvalue of |
| type `const error_code` and `n` is an lvalue of type `const int`. |
| |
| [heading Examples] |
| |
| A free function as a signal handler: |
| |
| void signal_handler( |
| const asio::error_code& ec, |
| int signal_number) |
| { |
| ... |
| } |
| |
| A signal handler function object: |
| |
| struct signal_handler |
| { |
| ... |
| void operator()( |
| const asio::error_code& ec, |
| int signal_number) |
| { |
| ... |
| } |
| ... |
| }; |
| |
| A lambda as a signal handler: |
| |
| my_signal_set.async_wait( |
| [](const asio::error_code& ec, |
| int signal_number) |
| { |
| ... |
| }); |
| |
| A non-static class member function adapted to a signal handler using |
| `std::bind()`: |
| |
| void my_class::signal_handler( |
| const asio::error_code& ec, |
| int signal_number) |
| { |
| ... |
| } |
| ... |
| my_signal_set.async_wait( |
| std::bind(&my_class::signal_handler, |
| this, std::placeholders::_1, |
| std::placeholders::_2)); |
| |
| A non-static class member function adapted to a signal handler using |
| `boost::bind()`: |
| |
| void my_class::signal_handler( |
| const asio::error_code& ec, |
| int signal_number) |
| { |
| ... |
| } |
| ... |
| my_signal_set.async_wait( |
| boost::bind(&my_class::signal_handler, |
| this, asio::placeholders::error, |
| asio::placeholders::signal_number)); |
| |
| [endsect] |