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<div class="body" role="main">222            223  <section id="high-level-api-index">224<h1>High-level API Index<a class="headerlink" href="#high-level-api-index" title="Link to this heading">¶</a></h1>225<p>This page lists all high-level async/await enabled asyncio APIs.</p>226<section id="tasks">227<h2>Tasks<a class="headerlink" href="#tasks" title="Link to this heading">¶</a></h2>228<p>Utilities to run asyncio programs, create Tasks, and229await on multiple things with timeouts.</p>230<table class="full-width-table docutils align-default">231<colgroup>232<col style="width: 50.0%" />233<col style="width: 50.0%" />234</colgroup>235<tbody>236<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-runner.html#asyncio.run" title="asyncio.run"><code class="xref py py-func docutils literal notranslate"><span class="pre">run()</span></code></a></p></td>237<td><p>Create event loop, run a coroutine, close the loop.</p></td>238</tr>239<tr class="row-even"><td><p><a class="reference internal" href="asyncio-runner.html#asyncio.Runner" title="asyncio.Runner"><code class="xref py py-class docutils literal notranslate"><span class="pre">Runner</span></code></a></p></td>240<td><p>A context manager that simplifies multiple async function calls.</p></td>241</tr>242<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">Task</span></code></a></p></td>243<td><p>Task object.</p></td>244</tr>245<tr class="row-even"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.TaskGroup" title="asyncio.TaskGroup"><code class="xref py py-class docutils literal notranslate"><span class="pre">TaskGroup</span></code></a></p></td>246<td><p>A context manager that holds a group of tasks. Provides247a convenient and reliable way to wait for all tasks in the group to248finish.</p></td>249</tr>250<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.create_task" title="asyncio.create_task"><code class="xref py py-func docutils literal notranslate"><span class="pre">create_task()</span></code></a></p></td>251<td><p>Start an asyncio Task, then returns it.</p></td>252</tr>253<tr class="row-even"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.current_task" title="asyncio.current_task"><code class="xref py py-func docutils literal notranslate"><span class="pre">current_task()</span></code></a></p></td>254<td><p>Return the current Task.</p></td>255</tr>256<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.all_tasks" title="asyncio.all_tasks"><code class="xref py py-func docutils literal notranslate"><span class="pre">all_tasks()</span></code></a></p></td>257<td><p>Return all tasks that are not yet finished for an event loop.</p></td>258</tr>259<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.sleep" title="asyncio.sleep"><code class="xref py py-func docutils literal notranslate"><span class="pre">sleep()</span></code></a></p></td>260<td><p>Sleep for a number of seconds.</p></td>261</tr>262<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.gather" title="asyncio.gather"><code class="xref py py-func docutils literal notranslate"><span class="pre">gather()</span></code></a></p></td>263<td><p>Schedule and wait for things concurrently.</p></td>264</tr>265<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.wait_for" title="asyncio.wait_for"><code class="xref py py-func docutils literal notranslate"><span class="pre">wait_for()</span></code></a></p></td>266<td><p>Run with a timeout.</p></td>267</tr>268<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.shield" title="asyncio.shield"><code class="xref py py-func docutils literal notranslate"><span class="pre">shield()</span></code></a></p></td>269<td><p>Shield from cancellation.</p></td>270</tr>271<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.wait" title="asyncio.wait"><code class="xref py py-func docutils literal notranslate"><span class="pre">wait()</span></code></a></p></td>272<td><p>Monitor for completion.</p></td>273</tr>274<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.timeout" title="asyncio.timeout"><code class="xref py py-func docutils literal notranslate"><span class="pre">timeout()</span></code></a></p></td>275<td><p>Run with a timeout. Useful in cases when <code class="docutils literal notranslate"><span class="pre">wait_for</span></code> is not suitable.</p></td>276</tr>277<tr class="row-even"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.to_thread" title="asyncio.to_thread"><code class="xref py py-func docutils literal notranslate"><span class="pre">to_thread()</span></code></a></p></td>278<td><p>Asynchronously run a function in a separate OS thread.</p></td>279</tr>280<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-task.html#asyncio.run_coroutine_threadsafe" title="asyncio.run_coroutine_threadsafe"><code class="xref py py-func docutils literal notranslate"><span class="pre">run_coroutine_threadsafe()</span></code></a></p></td>281<td><p>Schedule a coroutine from another OS thread.</p></td>282</tr>283<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">for</span> <span class="pre">in</span></code> <a class="reference internal" href="asyncio-task.html#asyncio.as_completed" title="asyncio.as_completed"><code class="xref py py-func docutils literal notranslate"><span class="pre">as_completed()</span></code></a></p></td>284<td><p>Monitor for completion with a <code class="docutils literal notranslate"><span class="pre">for</span></code> loop.</p></td>285</tr>286</tbody>287</table>288<p class="rubric">Examples</p>289<ul class="simple">290<li><p><a class="reference internal" href="asyncio-task.html#asyncio-example-gather"><span class="std std-ref">Using asyncio.gather() to run things in parallel</span></a>.</p></li>291<li><p><a class="reference internal" href="asyncio-task.html#asyncio-example-waitfor"><span class="std std-ref">Using asyncio.wait_for() to enforce a timeout</span></a>.</p></li>292<li><p><a class="reference internal" href="asyncio-task.html#asyncio-example-task-cancel"><span class="std std-ref">Cancellation</span></a>.</p></li>293<li><p><a class="reference internal" href="asyncio-task.html#asyncio-example-sleep"><span class="std std-ref">Using asyncio.sleep()</span></a>.</p></li>294<li><p>See also the main <a class="reference internal" href="asyncio-task.html#coroutine"><span class="std std-ref">Tasks documentation page</span></a>.</p></li>295</ul>296</section>297<section id="queues">298<h2>Queues<a class="headerlink" href="#queues" title="Link to this heading">¶</a></h2>299<p>Queues should be used to distribute work amongst multiple asyncio Tasks,300implement connection pools, and pub/sub patterns.</p>301<table class="full-width-table docutils align-default">302<colgroup>303<col style="width: 50.0%" />304<col style="width: 50.0%" />305</colgroup>306<tbody>307<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-queue.html#asyncio.Queue" title="asyncio.Queue"><code class="xref py py-class docutils literal notranslate"><span class="pre">Queue</span></code></a></p></td>308<td><p>A FIFO queue.</p></td>309</tr>310<tr class="row-even"><td><p><a class="reference internal" href="asyncio-queue.html#asyncio.PriorityQueue" title="asyncio.PriorityQueue"><code class="xref py py-class docutils literal notranslate"><span class="pre">PriorityQueue</span></code></a></p></td>311<td><p>A priority queue.</p></td>312</tr>313<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-queue.html#asyncio.LifoQueue" title="asyncio.LifoQueue"><code class="xref py py-class docutils literal notranslate"><span class="pre">LifoQueue</span></code></a></p></td>314<td><p>A LIFO queue.</p></td>315</tr>316</tbody>317</table>318<p class="rubric">Examples</p>319<ul class="simple">320<li><p><a class="reference internal" href="asyncio-queue.html#asyncio-example-queue-dist"><span class="std std-ref">Using asyncio.Queue to distribute workload between several321Tasks</span></a>.</p></li>322<li><p>See also the <a class="reference internal" href="asyncio-queue.html#asyncio-queues"><span class="std std-ref">Queues documentation page</span></a>.</p></li>323</ul>324</section>325<section id="subprocesses">326<h2>Subprocesses<a class="headerlink" href="#subprocesses" title="Link to this heading">¶</a></h2>327<p>Utilities to spawn subprocesses and run shell commands.</p>328<table class="full-width-table docutils align-default">329<colgroup>330<col style="width: 50.0%" />331<col style="width: 50.0%" />332</colgroup>333<tbody>334<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-subprocess.html#asyncio.create_subprocess_exec" title="asyncio.create_subprocess_exec"><code class="xref py py-func docutils literal notranslate"><span class="pre">create_subprocess_exec()</span></code></a></p></td>335<td><p>Create a subprocess.</p></td>336</tr>337<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-subprocess.html#asyncio.create_subprocess_shell" title="asyncio.create_subprocess_shell"><code class="xref py py-func docutils literal notranslate"><span class="pre">create_subprocess_shell()</span></code></a></p></td>338<td><p>Run a shell command.</p></td>339</tr>340</tbody>341</table>342<p class="rubric">Examples</p>343<ul class="simple">344<li><p><a class="reference internal" href="asyncio-subprocess.html#asyncio-example-subprocess-shell"><span class="std std-ref">Executing a shell command</span></a>.</p></li>345<li><p>See also the <a class="reference internal" href="asyncio-subprocess.html#asyncio-subprocess"><span class="std std-ref">subprocess APIs</span></a>346documentation.</p></li>347</ul>348</section>349<section id="streams">350<h2>Streams<a class="headerlink" href="#streams" title="Link to this heading">¶</a></h2>351<p>High-level APIs to work with network IO.</p>352<table class="full-width-table docutils align-default">353<colgroup>354<col style="width: 50.0%" />355<col style="width: 50.0%" />356</colgroup>357<tbody>358<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-stream.html#asyncio.open_connection" title="asyncio.open_connection"><code class="xref py py-func docutils literal notranslate"><span class="pre">open_connection()</span></code></a></p></td>359<td><p>Establish a TCP connection.</p></td>360</tr>361<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-stream.html#asyncio.open_unix_connection" title="asyncio.open_unix_connection"><code class="xref py py-func docutils literal notranslate"><span class="pre">open_unix_connection()</span></code></a></p></td>362<td><p>Establish a Unix socket connection.</p></td>363</tr>364<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-stream.html#asyncio.start_server" title="asyncio.start_server"><code class="xref py py-func docutils literal notranslate"><span class="pre">start_server()</span></code></a></p></td>365<td><p>Start a TCP server.</p></td>366</tr>367<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">await</span></code> <a class="reference internal" href="asyncio-stream.html#asyncio.start_unix_server" title="asyncio.start_unix_server"><code class="xref py py-func docutils literal notranslate"><span class="pre">start_unix_server()</span></code></a></p></td>368<td><p>Start a Unix socket server.</p></td>369</tr>370<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-stream.html#asyncio.StreamReader" title="asyncio.StreamReader"><code class="xref py py-class docutils literal notranslate"><span class="pre">StreamReader</span></code></a></p></td>371<td><p>High-level async/await object to receive network data.</p></td>372</tr>373<tr class="row-even"><td><p><a class="reference internal" href="asyncio-stream.html#asyncio.StreamWriter" title="asyncio.StreamWriter"><code class="xref py py-class docutils literal notranslate"><span class="pre">StreamWriter</span></code></a></p></td>374<td><p>High-level async/await object to send network data.</p></td>375</tr>376</tbody>377</table>378<p class="rubric">Examples</p>379<ul class="simple">380<li><p><a class="reference internal" href="asyncio-stream.html#asyncio-example-stream"><span class="std std-ref">Example TCP client</span></a>.</p></li>381<li><p>See also the <a class="reference internal" href="asyncio-stream.html#asyncio-streams"><span class="std std-ref">streams APIs</span></a>382documentation.</p></li>383</ul>384</section>385<section id="synchronization">386<h2>Synchronization<a class="headerlink" href="#synchronization" title="Link to this heading">¶</a></h2>387<p>Threading-like synchronization primitives that can be used in Tasks.</p>388<table class="full-width-table docutils align-default">389<colgroup>390<col style="width: 50.0%" />391<col style="width: 50.0%" />392</colgroup>393<tbody>394<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.Lock" title="asyncio.Lock"><code class="xref py py-class docutils literal notranslate"><span class="pre">Lock</span></code></a></p></td>395<td><p>A mutex lock.</p></td>396</tr>397<tr class="row-even"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.Event" title="asyncio.Event"><code class="xref py py-class docutils literal notranslate"><span class="pre">Event</span></code></a></p></td>398<td><p>An event object.</p></td>399</tr>400<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.Condition" title="asyncio.Condition"><code class="xref py py-class docutils literal notranslate"><span class="pre">Condition</span></code></a></p></td>401<td><p>A condition object.</p></td>402</tr>403<tr class="row-even"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.Semaphore" title="asyncio.Semaphore"><code class="xref py py-class docutils literal notranslate"><span class="pre">Semaphore</span></code></a></p></td>404<td><p>A semaphore.</p></td>405</tr>406<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.BoundedSemaphore" title="asyncio.BoundedSemaphore"><code class="xref py py-class docutils literal notranslate"><span class="pre">BoundedSemaphore</span></code></a></p></td>407<td><p>A bounded semaphore.</p></td>408</tr>409<tr class="row-even"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.Barrier" title="asyncio.Barrier"><code class="xref py py-class docutils literal notranslate"><span class="pre">Barrier</span></code></a></p></td>410<td><p>A barrier object.</p></td>411</tr>412</tbody>413</table>414<p class="rubric">Examples</p>415<ul class="simple">416<li><p><a class="reference internal" href="asyncio-sync.html#asyncio-example-sync-event"><span class="std std-ref">Using asyncio.Event</span></a>.</p></li>417<li><p><a class="reference internal" href="asyncio-sync.html#asyncio-example-barrier"><span class="std std-ref">Using asyncio.Barrier</span></a>.</p></li>418<li><p>See also the documentation of asyncio419<a class="reference internal" href="asyncio-sync.html#asyncio-sync"><span class="std std-ref">synchronization primitives</span></a>.</p></li>420</ul>421</section>422<section id="exceptions">423<h2>Exceptions<a class="headerlink" href="#exceptions" title="Link to this heading">¶</a></h2>424<table class="full-width-table docutils align-default">425<colgroup>426<col style="width: 50.0%" />427<col style="width: 50.0%" />428</colgroup>429<tbody>430<tr class="row-odd"><td><p><a class="reference internal" href="asyncio-exceptions.html#asyncio.CancelledError" title="asyncio.CancelledError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">asyncio.CancelledError</span></code></a></p></td>431<td><p>Raised when a Task is cancelled. See also <a class="reference internal" href="asyncio-task.html#asyncio.Task.cancel" title="asyncio.Task.cancel"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Task.cancel()</span></code></a>.</p></td>432</tr>433<tr class="row-even"><td><p><a class="reference internal" href="asyncio-sync.html#asyncio.BrokenBarrierError" title="asyncio.BrokenBarrierError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">asyncio.BrokenBarrierError</span></code></a></p></td>434<td><p>Raised when a Barrier is broken. See also <a class="reference internal" href="asyncio-sync.html#asyncio.Barrier.wait" title="asyncio.Barrier.wait"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Barrier.wait()</span></code></a>.</p></td>435</tr>436</tbody>437</table>438<p class="rubric">Examples</p>439<ul class="simple">440<li><p><a class="reference internal" href="asyncio-task.html#asyncio-example-task-cancel"><span class="std std-ref">Handling CancelledError to run code on cancellation request</span></a>.</p></li>441<li><p>See also the full list of442<a class="reference internal" href="asyncio-exceptions.html#asyncio-exceptions"><span class="std std-ref">asyncio-specific exceptions</span></a>.</p></li>443</ul>444</section>445</section>446 447 448            <div class="clearer"></div>449          </div>450        </div>451      </div>452      <div class="sphinxsidebar" role="navigation" aria-label="Main">453        <div class="sphinxsidebarwrapper">454  <div>455    <h3><a href="../contents.html">Table of Contents</a></h3>456    <ul>457<li><a class="reference internal" href="#">High-level API Index</a><ul>458<li><a class="reference internal" href="#tasks">Tasks</a></li>459<li><a class="reference internal" href="#queues">Queues</a></li>460<li><a class="reference internal" href="#subprocesses">Subprocesses</a></li>461<li><a class="reference internal" href="#streams">Streams</a></li>462<li><a class="reference internal" href="#synchronization">Synchronization</a></li>463<li><a class="reference internal" href="#exceptions">Exceptions</a></li>464</ul>465</li>466</ul>467 468  </div>469  <div>470    <h4>Previous topic</h4>471    <p class="topless"><a href="asyncio-extending.html"472                          title="previous chapter">Extending</a></p>473  </div>474  <div>475    <h4>Next topic</h4>476    <p class="topless"><a href="asyncio-llapi-index.html"477                          title="next chapter">Low-level API Index</a></p>478  </div>479  <script>480    document.addEventListener('DOMContentLoaded', () => {481        const title = document.querySelector('meta[property="og:title"]').content;482        const elements = document.querySelectorAll('.improvepage');483        const pageurl = window.location.href.split('?')[0];484        elements.forEach(element => {485            const url = new URL(element.href.split('?')[0].replace("-nojs", ""));486            url.searchParams.set('pagetitle', title);487            url.searchParams.set('pageurl', pageurl);488            url.searchParams.set('pagesource', "library/asyncio-api-index.rst");489            element.href = url.toString();490        });491    });492  </script>493  <div role="note" aria-label="source link">494    <h3>This page</h3>495    <ul class="this-page-menu">496      <li><a href="../bugs.html">Report a bug</a></li>497      <li><a class="improvepage" href="../improve-page-nojs.html">Improve this page</a></li>498      <li>499        <a href="https://github.com/python/cpython/blob/main/Doc/library/asyncio-api-index.rst?plain=1"500            rel="nofollow">Show source501        </a>502      </li>503      504    </ul>505  </div>506        </div>507<div id="sidebarbutton" title="Collapse sidebar">508<span>«</span>509</div>510 511      </div>512      <div class="clearer"></div>513    </div>  514    <div class="related" role="navigation" aria-label="Related">515      <h3>Navigation</h3>516      <ul>517        <li class="right" style="margin-right: 10px">518          <a href="../genindex.html" title="General Index"519             >index</a></li>520        <li class="right" >521          <a href="../py-modindex.html" title="Python Module Index"522             >modules</a> |</li>523        <li class="right" >524          <a href="asyncio-llapi-index.html" title="Low-level API Index"525             >next</a> |</li>526        <li class="right" >527          <a href="asyncio-extending.html" title="Extending"528             >previous</a> |</li>529 530          <li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; 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