| <!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="A multi-producer, single-consumer queue for sending values across asynchronous tasks."><meta name="keywords" content="rust, rustlang, rust-lang, mpsc"><title>futures::channel::mpsc - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../normalize.css"><link rel="stylesheet" href="../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../ayu.css" disabled><link rel="stylesheet" href="../../../dark.css" disabled><link rel="stylesheet" href="../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../storage.js"></script><script defer src="../../../main.js"></script><noscript><link rel="stylesheet" href="../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../favicon.svg"></head><body class="rustdoc mod"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../../../futures/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../../../futures/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">Module mpsc</a></h2><div class="sidebar-elems"><section><ul class="block"><li><a href="#structs">Structs</a></li><li><a href="#functions">Functions</a></li></ul></section></div></nav><main><div class="width-limiter"><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn">Module <a href="../../index.html">futures</a>::<wbr><a href="../index.html">channel</a>::<wbr><a class="mod" href="#">mpsc</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../../../src/futures_channel/lib.rs.html#39">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>A multi-producer, single-consumer queue for sending values across |
| asynchronous tasks.</p> |
| <p>Similarly to the <code>std</code>, channel creation provides <a href="struct.Receiver.html"><code>Receiver</code></a> and |
| <a href="struct.Sender.html"><code>Sender</code></a> handles. <a href="struct.Receiver.html"><code>Receiver</code></a> implements <a href="../../futures_core/stream/trait.Stream.html"><code>Stream</code></a> and allows a task to |
| read values out of the channel. If there is no message to read from the |
| channel, the current task will be notified when a new value is sent. |
| <a href="struct.Sender.html"><code>Sender</code></a> implements the <code>Sink</code> trait and allows a task to send messages into |
| the channel. If the channel is at capacity, the send will be rejected and |
| the task will be notified when additional capacity is available. In other |
| words, the channel provides backpressure.</p> |
| <p>Unbounded channels are also available using the <code>unbounded</code> constructor.</p> |
| <h2 id="disconnection"><a href="#disconnection">Disconnection</a></h2> |
| <p>When all <a href="struct.Sender.html"><code>Sender</code></a> handles have been dropped, it is no longer |
| possible to send values into the channel. This is considered the termination |
| event of the stream. As such, <a href="../../futures_core/stream/trait.Stream.html#tymethod.poll_next"><code>Receiver::poll_next</code></a> |
| will return <code>Ok(Ready(None))</code>.</p> |
| <p>If the <a href="struct.Receiver.html"><code>Receiver</code></a> handle is dropped, then messages can no longer |
| be read out of the channel. In this case, all further attempts to send will |
| result in an error.</p> |
| <h2 id="clean-shutdown"><a href="#clean-shutdown">Clean Shutdown</a></h2> |
| <p>If the <a href="struct.Receiver.html"><code>Receiver</code></a> is simply dropped, then it is possible for |
| there to be messages still in the channel that will not be processed. As |
| such, it is usually desirable to perform a “clean” shutdown. To do this, the |
| receiver will first call <code>close</code>, which will prevent any further messages to |
| be sent into the channel. Then, the receiver consumes the channel to |
| completion, at which point the receiver can be dropped.</p> |
| </div></details><h2 id="structs" class="small-section-header"><a href="#structs">Structs</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.Receiver.html" title="futures::channel::mpsc::Receiver struct">Receiver</a></div><div class="item-right docblock-short">The receiving end of a bounded mpsc channel.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.SendError.html" title="futures::channel::mpsc::SendError struct">SendError</a></div><div class="item-right docblock-short">The error type for <a href="struct.Sender.html"><code>Sender</code>s</a> used as <code>Sink</code>s.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.Sender.html" title="futures::channel::mpsc::Sender struct">Sender</a></div><div class="item-right docblock-short">The transmission end of a bounded mpsc channel.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.TryRecvError.html" title="futures::channel::mpsc::TryRecvError struct">TryRecvError</a></div><div class="item-right docblock-short">The error type returned from <a href="struct.Receiver.html#method.try_next"><code>try_next</code></a>.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.TrySendError.html" title="futures::channel::mpsc::TrySendError struct">TrySendError</a></div><div class="item-right docblock-short">The error type returned from <a href="struct.Sender.html#method.try_send"><code>try_send</code></a>.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.UnboundedReceiver.html" title="futures::channel::mpsc::UnboundedReceiver struct">UnboundedReceiver</a></div><div class="item-right docblock-short">The receiving end of an unbounded mpsc channel.</div></div><div class="item-row"><div class="item-left module-item"><a class="struct" href="struct.UnboundedSender.html" title="futures::channel::mpsc::UnboundedSender struct">UnboundedSender</a></div><div class="item-right docblock-short">The transmission end of an unbounded mpsc channel.</div></div></div><h2 id="functions" class="small-section-header"><a href="#functions">Functions</a></h2><div class="item-table"><div class="item-row"><div class="item-left module-item"><a class="fn" href="fn.channel.html" title="futures::channel::mpsc::channel fn">channel</a></div><div class="item-right docblock-short">Creates a bounded mpsc channel for communicating between asynchronous tasks.</div></div><div class="item-row"><div class="item-left module-item"><a class="fn" href="fn.unbounded.html" title="futures::channel::mpsc::unbounded fn">unbounded</a></div><div class="item-right docblock-short">Creates an unbounded mpsc channel for communicating between asynchronous |
| tasks.</div></div></div></section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="futures" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
