|
|
<!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 `get` fn in crate `num_cpus`."><meta name="keywords" content="rust, rustlang, rust-lang, get"><title>num_cpus::get - 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><noscript><link rel="stylesheet" href="../noscript.css"></noscript><link rel="shortcut icon" href="../favicon.ico"><style type="text/css">#crate-search{background-image:url("../down-arrow.svg");}</style></head><body class="rustdoc fn"><!--[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><a href='../num_cpus/index.html'><div class='logo-container'><img src='../rust-logo.png' alt='logo'></div></a><div class="sidebar-elems"><p class='location'><a href='index.html'>num_cpus</a></p><script>window.sidebarCurrent = {name: 'get', ty: 'fn', 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"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"></div><a id="settings-menu" href="../settings.html"><img src="../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><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/num_cpus/lib.rs.html#68-70' title='goto source code'>[src]</a></span><span class='in-band'>Function <a href='index.html'>num_cpus</a>::<wbr><a class="fn" href=''>get</a></span></h1><pre class='rust fn'>pub fn get() -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a></pre><div class='docblock'><p>Returns the number of available CPUs of the current system.</p>
|
|
|
<p>This function will get the number of logical cores. Sometimes this is different from the number
|
|
|
of physical cores (See <a href="https://en.wikipedia.org/wiki/Simultaneous_multithreading">Simultaneous multithreading on Wikipedia</a>).</p>
|
|
|
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
|
|
|
<div class="example-wrap"><pre class="rust rust-example-rendered">
|
|
|
<span class="kw">let</span> <span class="ident">cpus</span> <span class="op">=</span> <span class="ident">num_cpus</span>::<span class="ident">get</span>();
|
|
|
<span class="kw">if</span> <span class="ident">cpus</span> <span class="op">></span> <span class="number">1</span> {
|
|
|
<span class="macro">println</span><span class="macro">!</span>(<span class="string">"We are on a multicore system with {} CPUs"</span>, <span class="ident">cpus</span>);
|
|
|
} <span class="kw">else</span> {
|
|
|
<span class="macro">println</span><span class="macro">!</span>(<span class="string">"We are on a single core system"</span>);
|
|
|
}</pre></div>
|
|
|
<h1 id="note" class="section-header"><a href="#note">Note</a></h1>
|
|
|
<p>This will check <a href="http://www.gnu.org/software/libc/manual/html_node/CPU-Affinity.html">sched affinity</a> on Linux, showing a lower number of CPUs if the current
|
|
|
thread does not have access to all the computer's CPUs. </p>
|
|
|
</div></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><p>Search multiple things at once by splitting your query with comma (e.g., <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../";window.currentCrate = "num_cpus";</script><script src="../aliases.js"></script><script src="../main.js"></script><script defer src="../search-index.js"></script></body></html> |
