290 lines
No EOL
16 KiB
HTML
290 lines
No EOL
16 KiB
HTML
<!DOCTYPE html>
|
||
<html lang="en">
|
||
<head>
|
||
<meta charset="utf-8">
|
||
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
||
<meta name="generator" content="rustdoc">
|
||
<meta name="description" content="API documentation for the Rust `current_thread` mod in crate `tokio`.">
|
||
<meta name="keywords" content="rust, rustlang, rust-lang, current_thread">
|
||
|
||
<title>tokio::executor::current_thread - Rust</title>
|
||
|
||
<link rel="stylesheet" type="text/css" href="../../../normalize.css">
|
||
<link rel="stylesheet" type="text/css" href="../../../rustdoc.css"
|
||
id="mainThemeStyle">
|
||
|
||
<link rel="stylesheet" type="text/css" href="../../../dark.css">
|
||
<link rel="stylesheet" type="text/css" href="../../../light.css" id="themeStyle">
|
||
<script src="../../../storage.js"></script>
|
||
|
||
|
||
|
||
|
||
</head>
|
||
<body class="rustdoc mod">
|
||
<!--[if lte IE 8]>
|
||
<div class="warning">
|
||
This old browser is unsupported and will most likely display funky
|
||
things.
|
||
</div>
|
||
<![endif]-->
|
||
|
||
|
||
|
||
<nav class="sidebar">
|
||
<div class="sidebar-menu">☰</div>
|
||
|
||
<p class='location'>Module current_thread</p><div class="sidebar-elems"><div class="block items"><ul><li><a href="#structs">Structs</a></li><li><a href="#functions">Functions</a></li></ul></div><p class='location'><a href='../../index.html'>tokio</a>::<wbr><a href='../index.html'>executor</a></p><script>window.sidebarCurrent = {name: 'current_thread', ty: 'mod', relpath: '../'};</script><script defer src="../sidebar-items.js"></script></div>
|
||
</nav>
|
||
|
||
<div class="theme-picker">
|
||
<button id="theme-picker" aria-label="Pick another theme!">
|
||
<img src="../../../brush.svg" width="18" alt="Pick another theme!">
|
||
</button>
|
||
<div id="theme-choices"></div>
|
||
</div>
|
||
<script src="../../../theme.js"></script>
|
||
<nav class="sub">
|
||
<form class="search-form js-only">
|
||
<div class="search-container">
|
||
<input class="search-input" name="search"
|
||
autocomplete="off"
|
||
placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
|
||
type="search">
|
||
</div>
|
||
</form>
|
||
</nav>
|
||
|
||
<section id='main' class="content"><h1 class='fqn'><span class='in-band'>Module <a href='../../index.html'>tokio</a>::<wbr><a href='../index.html'>executor</a>::<wbr><a class="mod" href=''>current_thread</a></span><span class='out-of-band'><span id='render-detail'>
|
||
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
|
||
[<span class='inner'>−</span>]
|
||
</a>
|
||
</span><a class='srclink' href='../../../src/tokio/executor/current_thread/mod.rs.html#1-835' title='goto source code'>[src]</a></span></h1><div class='docblock'><p>Execute many tasks concurrently on the current thread.</p>
|
||
<p><a href="struct.CurrentThread.html"><code>CurrentThread</code></a> is an executor that keeps tasks on the same thread that
|
||
they were spawned from. This allows it to execute futures that are not
|
||
<code>Send</code>.</p>
|
||
<p>A single <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> instance is able to efficiently manage a large
|
||
number of tasks and will attempt to schedule all tasks fairly.</p>
|
||
<p>All tasks that are being managed by a <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> executor are able to
|
||
spawn additional tasks by calling <a href="fn.spawn.html"><code>spawn</code></a>. This function only works from
|
||
within the context of a running <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> instance.</p>
|
||
<p>The easiest way to start a new <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> executor is to call
|
||
<a href="fn.block_on_all.html"><code>block_on_all</code></a> with an initial task to seed the executor.</p>
|
||
<p>For example:</p>
|
||
|
||
<pre class="rust rust-example-rendered">
|
||
<span class="kw">use</span> <span class="ident">futures</span>::<span class="ident">future</span>::<span class="ident">lazy</span>;
|
||
|
||
<span class="comment">// Calling execute here results in a panic</span>
|
||
<span class="comment">// current_thread::spawn(my_future);</span>
|
||
|
||
<span class="ident">current_thread</span>::<span class="ident">block_on_all</span>(<span class="ident">lazy</span>(<span class="op">||</span> {
|
||
<span class="comment">// The execution context is setup, futures may be executed.</span>
|
||
<span class="ident">current_thread</span>::<span class="ident">spawn</span>(<span class="ident">lazy</span>(<span class="op">||</span> {
|
||
<span class="macro">println</span><span class="macro">!</span>(<span class="string">"called from the current thread executor"</span>);
|
||
<span class="prelude-val">Ok</span>(())
|
||
}));
|
||
|
||
<span class="prelude-val">Ok</span>::<span class="op"><</span><span class="kw">_</span>, ()<span class="op">></span>(())
|
||
}));</pre>
|
||
<p>The <code>block_on_all</code> function will block the current thread until <strong>all</strong>
|
||
tasks that have been spawned onto the <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> instance have
|
||
completed.</p>
|
||
<p>More fine-grain control can be achieved by using <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> directly.</p>
|
||
|
||
<pre class="rust rust-example-rendered">
|
||
<span class="kw">use</span> <span class="ident">futures</span>::<span class="ident">future</span>::{<span class="ident">lazy</span>, <span class="ident">empty</span>};
|
||
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">time</span>::<span class="ident">Duration</span>;
|
||
|
||
<span class="comment">// Calling execute here results in a panic</span>
|
||
<span class="comment">// current_thread::spawn(my_future);</span>
|
||
|
||
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">current_thread</span> <span class="op">=</span> <span class="ident">CurrentThread</span>::<span class="ident">new</span>();
|
||
|
||
<span class="comment">// Spawn a task, the task is not executed yet.</span>
|
||
<span class="ident">current_thread</span>.<span class="ident">spawn</span>(<span class="ident">lazy</span>(<span class="op">||</span> {
|
||
<span class="macro">println</span><span class="macro">!</span>(<span class="string">"Spawning a task"</span>);
|
||
<span class="prelude-val">Ok</span>(())
|
||
}));
|
||
|
||
<span class="comment">// Spawn a task that never completes</span>
|
||
<span class="ident">current_thread</span>.<span class="ident">spawn</span>(<span class="ident">empty</span>());
|
||
|
||
<span class="comment">// Run the executor, but only until the provided future completes. This</span>
|
||
<span class="comment">// provides the opportunity to start executing previously spawned tasks.</span>
|
||
<span class="kw">let</span> <span class="ident">res</span> <span class="op">=</span> <span class="ident">current_thread</span>.<span class="ident">block_on</span>(<span class="ident">lazy</span>(<span class="op">||</span> {
|
||
<span class="prelude-val">Ok</span>::<span class="op"><</span><span class="kw">_</span>, ()<span class="op">></span>(<span class="string">"Hello"</span>)
|
||
})).<span class="ident">unwrap</span>();
|
||
|
||
<span class="comment">// Now, run the executor for *at most* 1 second. Since a task was spawned</span>
|
||
<span class="comment">// that never completes, this function will return with an error.</span>
|
||
<span class="ident">current_thread</span>.<span class="ident">run_timeout</span>(<span class="ident">Duration</span>::<span class="ident">from_secs</span>(<span class="number">1</span>)).<span class="ident">unwrap_err</span>();</pre>
|
||
<h1 id="execution-model" class="section-header"><a href="#execution-model">Execution model</a></h1>
|
||
<p>Internally, <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> maintains a queue. When one of its tasks is
|
||
notified, the task gets added to the queue. The executor will pop tasks from
|
||
the queue and call <a href="https://docs.rs/futures/0.1/futures/future/trait.Future.html#tymethod.poll"><code>Future::poll</code></a>. If the task gets notified while it is
|
||
being executed, it won't get re-executed until all other tasks currently in
|
||
the queue get polled.</p>
|
||
<p>Before the task is polled, a thread-local variable referencing the current
|
||
<a href="struct.CurrentThread.html"><code>CurrentThread</code></a> instance is set. This enables <a href="fn.spawn.html"><code>spawn</code></a> to spawn new tasks
|
||
onto the same executor without having to thread through a handle value.</p>
|
||
<p>If the <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> instance still has uncompleted tasks, but none of
|
||
these tasks are ready to be polled, the current thread is put to sleep. When
|
||
a task is notified, the thread is woken up and processing resumes.</p>
|
||
<p>All tasks managed by <a href="struct.CurrentThread.html"><code>CurrentThread</code></a> remain on the current thread. When a
|
||
task completes, it is dropped.</p>
|
||
</div><h2 id='structs' class='section-header'><a href="#structs">Structs</a></h2>
|
||
<table>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.BlockError.html"
|
||
title='struct tokio::executor::current_thread::BlockError'>BlockError</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Error returned by the <code>block_on</code> function.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.CurrentThread.html"
|
||
title='struct tokio::executor::current_thread::CurrentThread'>CurrentThread</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Executes tasks on the current thread</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.Entered.html"
|
||
title='struct tokio::executor::current_thread::Entered'>Entered</a></td>
|
||
<td class='docblock-short'>
|
||
<p>A <code>CurrentThread</code> instance bound to a supplied execution context.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.Handle.html"
|
||
title='struct tokio::executor::current_thread::Handle'>Handle</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Handle to spawn a future on the corresponding <code>CurrentThread</code> instance</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.RunError.html"
|
||
title='struct tokio::executor::current_thread::RunError'>RunError</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Error returned by the <code>run</code> function.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.RunTimeoutError.html"
|
||
title='struct tokio::executor::current_thread::RunTimeoutError'>RunTimeoutError</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Error returned by the <code>run_timeout</code> function.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.TaskExecutor.html"
|
||
title='struct tokio::executor::current_thread::TaskExecutor'>TaskExecutor</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Executes futures on the current thread.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.Turn.html"
|
||
title='struct tokio::executor::current_thread::Turn'>Turn</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Returned by the <code>turn</code> function.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="struct" href="struct.TurnError.html"
|
||
title='struct tokio::executor::current_thread::TurnError'>TurnError</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Error returned by the <code>turn</code> function.</p>
|
||
|
||
</td>
|
||
</tr></table><h2 id='functions' class='section-header'><a href="#functions">Functions</a></h2>
|
||
<table>
|
||
<tr class=' module-item'>
|
||
<td><a class="fn" href="fn.block_on_all.html"
|
||
title='fn tokio::executor::current_thread::block_on_all'>block_on_all</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Run the executor bootstrapping the execution with the provided future.</p>
|
||
|
||
</td>
|
||
</tr>
|
||
<tr class=' module-item'>
|
||
<td><a class="fn" href="fn.spawn.html"
|
||
title='fn tokio::executor::current_thread::spawn'>spawn</a></td>
|
||
<td class='docblock-short'>
|
||
<p>Executes a future on the current thread.</p>
|
||
|
||
</td>
|
||
</tr></table></section>
|
||
<section id='search' class="content hidden"></section>
|
||
|
||
<section class="footer"></section>
|
||
|
||
<aside id="help" class="hidden">
|
||
<div>
|
||
<h1 class="hidden">Help</h1>
|
||
|
||
<div class="shortcuts">
|
||
<h2>Keyboard Shortcuts</h2>
|
||
|
||
<dl>
|
||
<dt><kbd>?</kbd></dt>
|
||
<dd>Show this help dialog</dd>
|
||
<dt><kbd>S</kbd></dt>
|
||
<dd>Focus the search field</dd>
|
||
<dt><kbd>↑</kbd></dt>
|
||
<dd>Move up in search results</dd>
|
||
<dt><kbd>↓</kbd></dt>
|
||
<dd>Move down in search results</dd>
|
||
<dt><kbd>↹</kbd></dt>
|
||
<dd>Switch tab</dd>
|
||
<dt><kbd>⏎</kbd></dt>
|
||
<dd>Go to active search result</dd>
|
||
<dt><kbd>+</kbd></dt>
|
||
<dd>Expand all sections</dd>
|
||
<dt><kbd>-</kbd></dt>
|
||
<dd>Collapse all sections</dd>
|
||
</dl>
|
||
</div>
|
||
|
||
<div class="infos">
|
||
<h2>Search Tricks</h2>
|
||
|
||
<p>
|
||
Prefix searches with a type followed by a colon (e.g.
|
||
<code>fn:</code>) to restrict the search to a given type.
|
||
</p>
|
||
|
||
<p>
|
||
Accepted types are: <code>fn</code>, <code>mod</code>,
|
||
<code>struct</code>, <code>enum</code>,
|
||
<code>trait</code>, <code>type</code>, <code>macro</code>,
|
||
and <code>const</code>.
|
||
</p>
|
||
|
||
<p>
|
||
Search functions by type signature (e.g.
|
||
<code>vec -> usize</code> or <code>* -> vec</code>)
|
||
</p>
|
||
</div>
|
||
</div>
|
||
</aside>
|
||
|
||
|
||
|
||
<script>
|
||
window.rootPath = "../../../";
|
||
window.currentCrate = "tokio";
|
||
</script>
|
||
<script src="../../../main.js"></script>
|
||
<script defer src="../../../search-index.js"></script>
|
||
</body>
|
||
</html> |