ISO/IEC TS 19216:2018

TECHNICAL ISO/IEC TS
SPECIFICATION 19216
First edition
2018-04
Programming Languages — C++
Extensions for Networking
Langages de programmation — Extensions C++ pour mise en réseau
Reference number
©
ISO/IEC 2018
© ISO/IEC 2018
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ii © ISO/IEC 2018 – All rights reserved

Contents
Foreword vi
1 Scope 1
2 Normative references 2
3 Terms and definitions 3
4 General Principles 4
4.1 Conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5 Namespaces and headers 5
6 Future plans (Informative) 6
7 Feature test macros (Informative) 7
8 Method of description (Informative) 8
8.1 Structure of each clause . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
8.2 Other conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
9 Error reporting 9
9.1 Synchronous operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
9.2 Asynchronous operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
9.3 Error conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
9.4 Suppression of signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
10 Library summary 11
11 Convenience header 13
11.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
12 Forward declarations 14
12.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
13 Asynchronous model 16
13.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
13.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
13.3 Class template async_result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
13.4 Class template async_completion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
13.5 Class template associated_allocator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
13.6 Function get_associated_allocator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
13.7 Class execution_context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
13.8 Class execution_context::service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
13.9 Class template is_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
13.10 Executor argument tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
13.11 uses_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
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13.12 Class template associated_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
13.13 Function get_associated_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
13.14 Class template executor_binder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
13.15 Function bind_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
13.16 Class template executor_work_guard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
13.17 Function make_work_guard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
13.18 Class system_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
13.19 Class system_context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
13.20 Class bad_executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
13.21 Class executor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
13.22 Function dispatch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
13.23 Function post . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
13.24 Function defer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
13.25 Class template strand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
13.26 Class template use_future_t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.27 Partial specialization of async_result for packaged_task . . . . . . . . . . . . . . . . . . . 59
14 Basic I/O services 61
14.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . 61
14.2 Class io_context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
14.3 Class io_context::executor_type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
15 Timers 67
15.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
15.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
15.3 Class template wait_traits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
15.4 Class template basic_waitable_timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
16 Buffers 73
16.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
16.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
16.3 Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
16.4 Class mutable_buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
16.5 Class const_buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
16.6 Buffer type traits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
16.7 Buffer sequence access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
16.8 Function buffer_size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
16.9 Function buffer_copy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
16.10 Buffer arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
16.11 Buffer creation functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
16.12 Class template dynamic_vector_buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
16.13 Class template dynamic_string_buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
16.14 Dynamic buffer creation functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
17 Buffer-oriented streams 92
17.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
17.2 Class transfer_all . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
17.3 Class transfer_at_least . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
17.4 Class transfer_exactly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
17.5 Synchronous read operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
17.6 Asynchronous read operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
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17.7 Synchronous write operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
17.8 Asynchronous write operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
17.9 Synchronous delimited read operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
17.10 Asynchronous delimited read operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
18 Sockets 104
18.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
18.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
18.3 Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
18.4 Class socket_base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
18.5 Socket options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
18.6 Class template basic_socket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
18.7 Class template basic_datagram_socket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
18.8 Class template basic_stream_socket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
18.9 Class template basic_socket_acceptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
19 Socket iostreams 157
19.1 Class template basic_socket_streambuf . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
19.2 Class template basic_socket_iostream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
20 Socket algorithms 164
20.1 Synchronous connect operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
20.2 Asynchronous connect operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
21 Internet protocol 167
21.1 Header synopsis . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
21.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
21.3 Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
21.4 Class ip::address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
21.5 Class ip::address_v4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
21.6 Class ip::address_v6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
21.7 Class ip::bad_address_cast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
21.8 Hash support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
21.9 Class template ip::basic_address_iterator specializations . . . . . . . . . . . . . . . . . 187
21.10 Class template ip::basic_address_range specializations . . . . . . . . . . . . . . . . . . . 188
21.11 Class template ip::network_v4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
21.12 Class template ip::network_v6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
21.13 Class template ip::basic_endpoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
21.14 Class template ip::basic_resolver_entry . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
21.15 Class template ip::basic_resolver_results . . . . . . . . . . . . . . . . . . . . . . . . . 201
21.16 Class ip::resolver_base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
21.17 Class template ip::basic_resolver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
21.18 Host name functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
21.19 Class ip::tcp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
21.20 Class ip::udp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
21.21 Internet socket options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Index 219
Index of library names 221
Index of implementation-defined behavior 227
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Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members
of ISO or IEC participate in the development of International Standards through technical committees
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technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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This document was prepared by Technical Committee ISO/IEC
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