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  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="beast.ref.boost__beast__basic_stream"></a><a class="link" href="boost__beast__basic_stream.html" title="basic_stream">basic_stream</a>
  28 </h4></div></div></div>
  29 <p>
  30         A stream socket wrapper with timeouts, an executor, and a rate limit policy.
  31       </p>
  32 <h5>
  33 <a name="beast.ref.boost__beast__basic_stream.h0"></a>
  34         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.synopsis"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.synopsis">Synopsis</a>
  35       </h5>
  36 <p>
  37         Defined in header <code class="literal">&lt;<a href="../../../../../../boost/beast/core/basic_stream.hpp" target="_top">boost/beast/core/basic_stream.hpp</a>&gt;</code>
  38       </p>
  39 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  40     <span class="keyword">class</span> <a href="../../../../../../doc/html/boost_asio/reference/Protocol.html" target="_top"><span class="emphasis"><em>Protocol</em></span></a><span class="special">,</span>
  41     <span class="keyword">class</span> <a href="../../../../../../doc/html/boost_asio/reference/Executor1.html" target="_top"><span class="emphasis"><em>Executor</em></span></a> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">executor</span><span class="special">,</span>
  42     <span class="keyword">class</span> <a class="link" href="../concepts/RatePolicy.html" title="RatePolicy"><span class="emphasis"><em>RatePolicy</em></span></a> <span class="special">=</span> <span class="identifier">unlimited_rate_policy</span><span class="special">&gt;</span>
  43 <span class="keyword">class</span> <span class="identifier">basic_stream</span>
  44 </pre>
  45 <h5>
  46 <a name="beast.ref.boost__beast__basic_stream.h1"></a>
  47         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.types"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.types">Types</a>
  48       </h5>
  49 <div class="informaltable"><table class="table">
  50 <colgroup>
  51 <col>
  52 <col>
  53 </colgroup>
  54 <thead><tr>
  55 <th>
  56                 <p>
  57                   Name
  58                 </p>
  59               </th>
  60 <th>
  61                 <p>
  62                   Description
  63                 </p>
  64               </th>
  65 </tr></thead>
  66 <tbody>
  67 <tr>
  68 <td>
  69                 <p>
  70                   <a class="link" href="boost__beast__basic_stream__rebind_executor.html" title="basic_stream::rebind_executor"><span class="bold"><strong>rebind_executor</strong></span></a>
  71                 </p>
  72               </td>
  73 <td>
  74                 <p>
  75                   Rebinds the stream type to another executor.
  76                 </p>
  77               </td>
  78 </tr>
  79 <tr>
  80 <td>
  81                 <p>
  82                   <a class="link" href="boost__beast__basic_stream/endpoint_type.html" title="basic_stream::endpoint_type"><span class="bold"><strong>endpoint_type</strong></span></a>
  83                 </p>
  84               </td>
  85 <td>
  86                 <p>
  87                   The endpoint type.
  88                 </p>
  89               </td>
  90 </tr>
  91 <tr>
  92 <td>
  93                 <p>
  94                   <a class="link" href="boost__beast__basic_stream/executor_type.html" title="basic_stream::executor_type"><span class="bold"><strong>executor_type</strong></span></a>
  95                 </p>
  96               </td>
  97 <td>
  98                 <p>
  99                   The type of the executor associated with the stream.
 100                 </p>
 101               </td>
 102 </tr>
 103 <tr>
 104 <td>
 105                 <p>
 106                   <a class="link" href="boost__beast__basic_stream/protocol_type.html" title="basic_stream::protocol_type"><span class="bold"><strong>protocol_type</strong></span></a>
 107                 </p>
 108               </td>
 109 <td>
 110                 <p>
 111                   The protocol type.
 112                 </p>
 113               </td>
 114 </tr>
 115 <tr>
 116 <td>
 117                 <p>
 118                   <a class="link" href="boost__beast__basic_stream/socket_type.html" title="basic_stream::socket_type"><span class="bold"><strong>socket_type</strong></span></a>
 119                 </p>
 120               </td>
 121 <td>
 122                 <p>
 123                   The type of the underlying socket.
 124                 </p>
 125               </td>
 126 </tr>
 127 </tbody>
 128 </table></div>
 129 <h5>
 130 <a name="beast.ref.boost__beast__basic_stream.h2"></a>
 131         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.member_functions"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.member_functions">Member Functions</a>
 132       </h5>
 133 <div class="informaltable"><table class="table">
 134 <colgroup>
 135 <col>
 136 <col>
 137 </colgroup>
 138 <thead><tr>
 139 <th>
 140                 <p>
 141                   Name
 142                 </p>
 143               </th>
 144 <th>
 145                 <p>
 146                   Description
 147                 </p>
 148               </th>
 149 </tr></thead>
 150 <tbody>
 151 <tr>
 152 <td>
 153                 <p>
 154                   <a class="link" href="boost__beast__basic_stream/async_connect.html" title="basic_stream::async_connect"><span class="bold"><strong>async_connect</strong></span></a>
 155                 </p>
 156               </td>
 157 <td>
 158                 <p>
 159                   Connect the stream to the specified endpoint asynchronously.
 160                 </p>
 161                 <p>
 162                   Establishes a connection by trying each endpoint in a sequence
 163                   asynchronously.
 164                 </p>
 165               </td>
 166 </tr>
 167 <tr>
 168 <td>
 169                 <p>
 170                   <a class="link" href="boost__beast__basic_stream/async_read_some.html" title="basic_stream::async_read_some"><span class="bold"><strong>async_read_some</strong></span></a>
 171                 </p>
 172               </td>
 173 <td>
 174                 <p>
 175                   Read some data asynchronously.
 176                 </p>
 177               </td>
 178 </tr>
 179 <tr>
 180 <td>
 181                 <p>
 182                   <a class="link" href="boost__beast__basic_stream/async_write_some.html" title="basic_stream::async_write_some"><span class="bold"><strong>async_write_some</strong></span></a>
 183                 </p>
 184               </td>
 185 <td>
 186                 <p>
 187                   Write some data asynchronously.
 188                 </p>
 189               </td>
 190 </tr>
 191 <tr>
 192 <td>
 193                 <p>
 194                   <a class="link" href="boost__beast__basic_stream/basic_stream.html" title="basic_stream::basic_stream"><span class="bold"><strong>basic_stream</strong></span></a>
 195                 </p>
 196               </td>
 197 <td>
 198                 <p>
 199                   Constructor.
 200                 </p>
 201                 <p>
 202                   Move constructor.
 203                 </p>
 204               </td>
 205 </tr>
 206 <tr>
 207 <td>
 208                 <p>
 209                   <a class="link" href="boost__beast__basic_stream/cancel.html" title="basic_stream::cancel"><span class="bold"><strong>cancel</strong></span></a>
 210                 </p>
 211               </td>
 212 <td>
 213                 <p>
 214                   Cancel all asynchronous operations associated with the socket.
 215                 </p>
 216               </td>
 217 </tr>
 218 <tr>
 219 <td>
 220                 <p>
 221                   <a class="link" href="boost__beast__basic_stream/close.html" title="basic_stream::close"><span class="bold"><strong>close</strong></span></a>
 222                 </p>
 223               </td>
 224 <td>
 225                 <p>
 226                   Close the timed stream.
 227                 </p>
 228               </td>
 229 </tr>
 230 <tr>
 231 <td>
 232                 <p>
 233                   <a class="link" href="boost__beast__basic_stream/connect.html" title="basic_stream::connect"><span class="bold"><strong>connect</strong></span></a>
 234                 </p>
 235               </td>
 236 <td>
 237                 <p>
 238                   Connect the stream to the specified endpoint.
 239                 </p>
 240                 <p>
 241                   Establishes a connection by trying each endpoint in a sequence.
 242                 </p>
 243               </td>
 244 </tr>
 245 <tr>
 246 <td>
 247                 <p>
 248                   <a class="link" href="boost__beast__basic_stream/expires_after.html" title="basic_stream::expires_after"><span class="bold"><strong>expires_after</strong></span></a>
 249                 </p>
 250               </td>
 251 <td>
 252                 <p>
 253                   Set the timeout for the next logical operation.
 254                 </p>
 255               </td>
 256 </tr>
 257 <tr>
 258 <td>
 259                 <p>
 260                   <a class="link" href="boost__beast__basic_stream/expires_at.html" title="basic_stream::expires_at"><span class="bold"><strong>expires_at</strong></span></a>
 261                 </p>
 262               </td>
 263 <td>
 264                 <p>
 265                   Set the timeout for the next logical operation.
 266                 </p>
 267               </td>
 268 </tr>
 269 <tr>
 270 <td>
 271                 <p>
 272                   <a class="link" href="boost__beast__basic_stream/expires_never.html" title="basic_stream::expires_never"><span class="bold"><strong>expires_never</strong></span></a>
 273                 </p>
 274               </td>
 275 <td>
 276                 <p>
 277                   Disable the timeout for the next logical operation.
 278                 </p>
 279               </td>
 280 </tr>
 281 <tr>
 282 <td>
 283                 <p>
 284                   <a class="link" href="boost__beast__basic_stream/get_executor.html" title="basic_stream::get_executor"><span class="bold"><strong>get_executor</strong></span></a>
 285                 </p>
 286               </td>
 287 <td>
 288                 <p>
 289                   Get the executor associated with the object.
 290                 </p>
 291               </td>
 292 </tr>
 293 <tr>
 294 <td>
 295                 <p>
 296                   <a class="link" href="boost__beast__basic_stream/operator_eq_.html" title="basic_stream::operator="><span class="bold"><strong>operator=</strong></span></a>
 297                 </p>
 298               </td>
 299 <td>
 300                 <p>
 301                   Move assignment (deleted).
 302                 </p>
 303               </td>
 304 </tr>
 305 <tr>
 306 <td>
 307                 <p>
 308                   <a class="link" href="boost__beast__basic_stream/rate_policy.html" title="basic_stream::rate_policy"><span class="bold"><strong>rate_policy</strong></span></a>
 309                 </p>
 310               </td>
 311 <td>
 312                 <p>
 313                   Returns the rate policy associated with the object.
 314                 </p>
 315               </td>
 316 </tr>
 317 <tr>
 318 <td>
 319                 <p>
 320                   <a class="link" href="boost__beast__basic_stream/read_some.html" title="basic_stream::read_some"><span class="bold"><strong>read_some</strong></span></a>
 321                 </p>
 322               </td>
 323 <td>
 324                 <p>
 325                   Read some data.
 326                 </p>
 327               </td>
 328 </tr>
 329 <tr>
 330 <td>
 331                 <p>
 332                   <a class="link" href="boost__beast__basic_stream/release_socket.html" title="basic_stream::release_socket"><span class="bold"><strong>release_socket</strong></span></a>
 333                 </p>
 334               </td>
 335 <td>
 336                 <p>
 337                   Release ownership of the underlying socket.
 338                 </p>
 339               </td>
 340 </tr>
 341 <tr>
 342 <td>
 343                 <p>
 344                   <a class="link" href="boost__beast__basic_stream/socket.html" title="basic_stream::socket"><span class="bold"><strong>socket</strong></span></a>
 345                 </p>
 346               </td>
 347 <td>
 348                 <p>
 349                   Return a reference to the underlying socket.
 350                 </p>
 351               </td>
 352 </tr>
 353 <tr>
 354 <td>
 355                 <p>
 356                   <a class="link" href="boost__beast__basic_stream/write_some.html" title="basic_stream::write_some"><span class="bold"><strong>write_some</strong></span></a>
 357                 </p>
 358               </td>
 359 <td>
 360                 <p>
 361                   Write some data.
 362                 </p>
 363               </td>
 364 </tr>
 365 <tr>
 366 <td>
 367                 <p>
 368                   <a class="link" href="boost__beast__basic_stream/basic_stream_dtor_.html" title="basic_stream::~basic_stream"><span class="bold"><strong>~basic_stream</strong></span></a>
 369                 </p>
 370               </td>
 371 <td>
 372                 <p>
 373                   Destructor.
 374                 </p>
 375               </td>
 376 </tr>
 377 </tbody>
 378 </table></div>
 379 <h5>
 380 <a name="beast.ref.boost__beast__basic_stream.h3"></a>
 381         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.description"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.description">Description</a>
 382       </h5>
 383 <p>
 384         This stream wraps a <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">basic_stream_socket</span></code> to provide the following
 385         features:
 386       </p>
 387 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 388 <li class="listitem">
 389             An <span class="emphasis"><em>Executor</em></span> may be associated with the stream, which
 390             will be used to invoke any completion handlers which do not already have
 391             an associated executor. This achieves support for <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1322r0.html" target="_top">[P1322R0]
 392             Networking TS enhancement to enable custom I/O executors</a>.
 393           </li>
 394 <li class="listitem">
 395             Timeouts may be specified for each logical asynchronous operation performing
 396             any reading, writing, or connecting.
 397           </li>
 398 <li class="listitem">
 399             A <span class="emphasis"><em>RatePolicy</em></span> may be associated with the stream,
 400             to implement rate limiting through the policy's interface.
 401           </li>
 402 </ul></div>
 403 <p>
 404         Although the stream supports multiple concurrent outstanding asynchronous
 405         operations, the stream object is not thread-safe. The caller is responsible
 406         for ensuring that the stream is accessed from only one thread at a time.
 407         This includes the times when the stream, and its underlying socket, are accessed
 408         by the networking implementation. To meet this thread safety requirement,
 409         all asynchronous operations must be performed by the stream within the same
 410         implicit strand (only one thread <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">io_context</span><span class="special">::</span><span class="identifier">run</span></code>)
 411         or within the same explicit strand, such as an instance of <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">strand</span></code>.
 412         Completion handlers with explicit associated executors (such as those arising
 413         from use of <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">bind_executor</span></code>) will be invoked by the stream
 414         using the associated executor. Otherwise, the completion handler will be
 415         invoked by the executor associated with the stream upon construction. The
 416         type of executor used with this stream must meet the following requirements:
 417       </p>
 418 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
 419             Function objects submitted to the executor shall never run concurrently
 420             with each other.
 421           </li></ul></div>
 422 <p>
 423         The executor type <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">strand</span></code> meets these requirements. Use of
 424         a strand as the executor in the stream class template offers an additional
 425         notational convenience: the strand does not need to be specified in each
 426         individual initiating function call. Unlike other stream wrappers, the underlying
 427         socket is accessed through the <a class="link" href="boost__beast__basic_stream/socket.html" title="basic_stream::socket"><code class="computeroutput"><span class="identifier">basic_stream</span><span class="special">::</span><span class="identifier">socket</span></code></a> member function instead of
 428         <code class="computeroutput"><span class="identifier">next_layer</span></code>. This causes the
 429         <a class="link" href="boost__beast__basic_stream.html" title="basic_stream"><code class="computeroutput"><span class="identifier">basic_stream</span></code></a>
 430         to be returned in calls to <a class="link" href="boost__beast__get_lowest_layer.html" title="get_lowest_layer"><code class="computeroutput"><span class="identifier">get_lowest_layer</span></code></a>.
 431       </p>
 432 <h5>
 433 <a name="beast.ref.boost__beast__basic_stream.h4"></a>
 434         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.usage"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.usage">Usage</a>
 435       </h5>
 436 <p>
 437         To use this stream declare an instance of the class. Then, before each logical
 438         operation for which a timeout is desired, call <a class="link" href="boost__beast__basic_stream/expires_after.html" title="basic_stream::expires_after"><code class="computeroutput"><span class="identifier">basic_stream</span><span class="special">::</span><span class="identifier">expires_after</span></code></a> with a duration, or
 439         call <a class="link" href="boost__beast__basic_stream/expires_at.html" title="basic_stream::expires_at"><code class="computeroutput"><span class="identifier">basic_stream</span><span class="special">::</span><span class="identifier">expires_at</span></code></a> with a time point. Alternatively,
 440         call <a class="link" href="boost__beast__basic_stream/expires_never.html" title="basic_stream::expires_never"><code class="computeroutput"><span class="identifier">basic_stream</span><span class="special">::</span><span class="identifier">expires_never</span></code></a> to disable the timeout
 441         for subsequent logical operations. A logical operation is any series of one
 442         or more direct or indirect calls to the timeout stream's asynchronous read,
 443         asynchronous write, or asynchronous connect functions. When a timeout is
 444         set and a mixed operation is performed (one that includes both reads and
 445         writes, for example) the timeout applies to all of the intermediate asynchronous
 446         operations used in the enclosing operation. This allows timeouts to be applied
 447         to stream algorithms which were not written specifically to allow for timeouts,
 448         when those algorithms are passed a timeout stream with a timeout set. When
 449         a timeout occurs the socket will be closed, canceling any pending I/O operations.
 450         The completion handlers for these canceled operations will be invoked with
 451         the error <a class="link" href="boost__beast__error.html" title="error"><code class="computeroutput"><span class="identifier">timeout</span></code></a>.
 452       </p>
 453 <h5>
 454 <a name="beast.ref.boost__beast__basic_stream.h5"></a>
 455         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.examples"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.examples">Examples</a>
 456       </h5>
 457 <p>
 458         This function reads an HTTP request with a timeout, then sends the HTTP response
 459         with a different timeout.
 460       </p>
 461 <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">process_http_1</span> <span class="special">(</span><span class="identifier">tcp_stream</span><span class="special">&amp;</span> <span class="identifier">stream</span><span class="special">,</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">yield_context</span> <span class="identifier">yield</span><span class="special">)</span>
 462 <span class="special">{</span>
 463     <span class="identifier">flat_buffer</span> <span class="identifier">buffer</span><span class="special">;</span>
 464     <span class="identifier">http</span><span class="special">::</span><span class="identifier">request</span><span class="special">&lt;</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">empty_body</span><span class="special">&gt;</span> <span class="identifier">req</span><span class="special">;</span>
 465
 466     <span class="comment">// Read the request, with a 15 second timeout</span>
 467     <span class="identifier">stream</span><span class="special">.</span><span class="identifier">expires_after</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">15</span><span class="special">));</span>
 468     <span class="identifier">http</span><span class="special">::</span><span class="identifier">async_read</span><span class="special">(</span><span class="identifier">stream</span><span class="special">,</span> <span class="identifier">buffer</span><span class="special">,</span> <span class="identifier">req</span><span class="special">,</span> <span class="identifier">yield</span><span class="special">);</span>
 469
 470     <span class="comment">// Calculate the response</span>
 471     <span class="identifier">http</span><span class="special">::</span><span class="identifier">response</span><span class="special">&lt;</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">string_body</span><span class="special">&gt;</span> <span class="identifier">res</span> <span class="special">=</span> <span class="identifier">make_response</span><span class="special">(</span><span class="identifier">req</span><span class="special">);</span>
 472
 473     <span class="comment">// Send the response, with a 30 second timeout.</span>
 474     <span class="identifier">stream</span><span class="special">.</span><span class="identifier">expires_after</span> <span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">30</span><span class="special">));</span>
 475     <span class="identifier">http</span><span class="special">::</span><span class="identifier">async_write</span> <span class="special">(</span><span class="identifier">stream</span><span class="special">,</span> <span class="identifier">res</span><span class="special">,</span> <span class="identifier">yield</span><span class="special">);</span>
 476 <span class="special">}</span>
 477 </pre>
 478 <p>
 479         The example above could be expressed using a single timeout with a simple
 480         modification. The function that follows first reads an HTTP request then
 481         sends the HTTP response, with a single timeout that applies to the entire
 482         combined operation of reading and writing:
 483       </p>
 484 <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">process_http_2</span> <span class="special">(</span><span class="identifier">tcp_stream</span><span class="special">&amp;</span> <span class="identifier">stream</span><span class="special">,</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">yield_context</span> <span class="identifier">yield</span><span class="special">)</span>
 485 <span class="special">{</span>
 486     <span class="identifier">flat_buffer</span> <span class="identifier">buffer</span><span class="special">;</span>
 487     <span class="identifier">http</span><span class="special">::</span><span class="identifier">request</span><span class="special">&lt;</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">empty_body</span><span class="special">&gt;</span> <span class="identifier">req</span><span class="special">;</span>
 488
 489     <span class="comment">// Require that the read and write combined take no longer than 30 seconds</span>
 490     <span class="identifier">stream</span><span class="special">.</span><span class="identifier">expires_after</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">30</span><span class="special">));</span>
 491
 492     <span class="identifier">http</span><span class="special">::</span><span class="identifier">async_read</span><span class="special">(</span><span class="identifier">stream</span><span class="special">,</span> <span class="identifier">buffer</span><span class="special">,</span> <span class="identifier">req</span><span class="special">,</span> <span class="identifier">yield</span><span class="special">);</span>
 493
 494     <span class="identifier">http</span><span class="special">::</span><span class="identifier">response</span><span class="special">&lt;</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">string_body</span><span class="special">&gt;</span> <span class="identifier">res</span> <span class="special">=</span> <span class="identifier">make_response</span><span class="special">(</span><span class="identifier">req</span><span class="special">);</span>
 495     <span class="identifier">http</span><span class="special">::</span><span class="identifier">async_write</span> <span class="special">(</span><span class="identifier">stream</span><span class="special">,</span> <span class="identifier">res</span><span class="special">,</span> <span class="identifier">yield</span><span class="special">);</span>
 496 <span class="special">}</span>
 497 </pre>
 498 <p>
 499         Some stream algorithms, such as <code class="computeroutput"><span class="identifier">ssl</span><span class="special">::</span><span class="identifier">stream</span><span class="special">::</span><span class="identifier">async_handshake</span></code>
 500         perform both reads and writes. A timeout set before calling the initiating
 501         function of such composite stream algorithms will apply to the entire composite
 502         operation. For example, a timeout may be set on performing the SSL handshake
 503         thusly:
 504       </p>
 505 <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">do_ssl_handshake</span> <span class="special">(</span><span class="identifier">net</span><span class="special">::</span><span class="identifier">ssl</span><span class="special">::</span><span class="identifier">stream</span><span class="special">&lt;</span><span class="identifier">tcp_stream</span><span class="special">&gt;&amp;</span> <span class="identifier">stream</span><span class="special">,</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">yield_context</span> <span class="identifier">yield</span><span class="special">)</span>
 506 <span class="special">{</span>
 507     <span class="comment">// Require that the SSL handshake take no longer than 10 seconds</span>
 508     <span class="identifier">stream</span><span class="special">.</span><span class="identifier">expires_after</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">10</span><span class="special">));</span>
 509
 510     <span class="identifier">stream</span><span class="special">.</span><span class="identifier">async_handshake</span><span class="special">(</span><span class="identifier">net</span><span class="special">::</span><span class="identifier">ssl</span><span class="special">::</span><span class="identifier">stream_base</span><span class="special">::</span><span class="identifier">client</span><span class="special">,</span> <span class="identifier">yield</span><span class="special">);</span>
 511 <span class="special">}</span>
 512 </pre>
 513 <h5>
 514 <a name="beast.ref.boost__beast__basic_stream.h6"></a>
 515         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.blocking_i_o"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.blocking_i_o">Blocking
 516         I/O</a>
 517       </h5>
 518 <p>
 519         Synchronous functions behave identically as that of the wrapped <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">basic_stream_socket</span></code>.
 520         Timeouts are not available when performing blocking calls.
 521       </p>
 522 <h5>
 523 <a name="beast.ref.boost__beast__basic_stream.h7"></a>
 524         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.template_parameters"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.template_parameters">Template
 525         Parameters</a>
 526       </h5>
 527 <div class="informaltable"><table class="table">
 528 <colgroup>
 529 <col>
 530 <col>
 531 </colgroup>
 532 <thead><tr>
 533 <th>
 534                 <p>
 535                   Type
 536                 </p>
 537               </th>
 538 <th>
 539                 <p>
 540                   Description
 541                 </p>
 542               </th>
 543 </tr></thead>
 544 <tbody>
 545 <tr>
 546 <td>
 547                 <p>
 548                   <code class="computeroutput"><span class="identifier">Protocol</span></code>
 549                 </p>
 550               </td>
 551 <td>
 552                 <p>
 553                   A type meeting the requirements of <span class="emphasis"><em>Protocol</em></span>
 554                   representing the protocol the protocol to use for the basic stream
 555                   socket. A common choice is <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span></code>.
 556                 </p>
 557               </td>
 558 </tr>
 559 <tr>
 560 <td>
 561                 <p>
 562                   <code class="computeroutput"><span class="identifier">Executor</span></code>
 563                 </p>
 564               </td>
 565 <td>
 566                 <p>
 567                   A type meeting the requirements of <span class="emphasis"><em>Executor</em></span>
 568                   to be used for submitting all completion handlers which do not
 569                   already have an associated executor. If this type is omitted, the
 570                   default of <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">executor</span></code>
 571                   will be used.
 572                 </p>
 573               </td>
 574 </tr>
 575 </tbody>
 576 </table></div>
 577 <h5>
 578 <a name="beast.ref.boost__beast__basic_stream.h8"></a>
 579         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.thread_safety"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.thread_safety">Thread
 580         Safety</a>
 581       </h5>
 582 <p>
 583         <span class="emphasis"><em>Distinct objects</em></span>: Safe.
 584       </p>
 585 <p>
 586         <span class="emphasis"><em>Shared objects</em></span>: Unsafe. The application must also ensure
 587         that all asynchronous operations are performed within the same implicit or
 588         explicit strand.
 589       </p>
 590 <h5>
 591 <a name="beast.ref.boost__beast__basic_stream.h9"></a>
 592         <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.see_also"></a></span><a class="link" href="boost__beast__basic_stream.html#beast.ref.boost__beast__basic_stream.see_also">See
 593         Also</a>
 594       </h5>
 595 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
 596             <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1322r0.html" target="_top">[P1322R0]
 597             Networking TS enhancement to enable custom I/O executors</a>.
 598           </li></ul></div>
 599 <p>
 600         Convenience header <code class="literal">&lt;<a href="../../../../../../boost/beast/core.hpp" target="_top">boost/beast/core.hpp</a>&gt;</code>
 601       </p>
 602 </div>
 603 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 604 <td align="left"></td>
 605 <td align="right"><div class="copyright-footer">Copyright &#169; 2016-2019 Vinnie
 606       Falco<p>
 607         Distributed under the Boost Software License, Version 1.0. (See accompanying
 608         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
 609       </p>
 610 </div></td>
 611 </tr></table>
 612 <hr>
 613 <div class="spirit-nav">
 614 <a accesskey="p" href="boost__beast__basic_multi_buffer__readable_bytes.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../ref.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="boost__beast__basic_stream/async_connect.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
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