Files
tantivy/fs2/trait.FileExt.html
2018-02-12 02:52:50 +00:00

205 lines
20 KiB
HTML
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!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 `FileExt` trait in crate `fs2`.">
<meta name="keywords" content="rust, rustlang, rust-lang, FileExt">
<title>fs2::FileExt - 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="../main.css" id="themeStyle">
<script src="../storage.js"></script>
</head>
<body class="rustdoc trait">
<!--[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">&#9776;</div>
<p class='location'>Trait FileExt</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#required-methods">Required Methods</a><div class="sidebar-links"><a href="#tymethod.duplicate">duplicate</a><a href="#tymethod.allocated_size">allocated_size</a><a href="#tymethod.allocate">allocate</a><a href="#tymethod.lock_shared">lock_shared</a><a href="#tymethod.lock_exclusive">lock_exclusive</a><a href="#tymethod.try_lock_shared">try_lock_shared</a><a href="#tymethod.try_lock_exclusive">try_lock_exclusive</a><a href="#tymethod.unlock">unlock</a></div><a class="sidebar-title" href="#foreign-impls">Implementations on Foreign Types</a><div class="sidebar-links"><a href="#impl-FileExt">File</a></div><a class="sidebar-title" href="#implementors">Implementors</a></div><p class='location'><a href='index.html'>fs2</a></p><script>window.sidebarCurrent = {name: 'FileExt', ty: 'trait', 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'>Trait <a href='index.html'>fs2</a>::<wbr><a class="trait" href=''>FileExt</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'>&#x2212;</span>]
</a>
</span><a class='srclink' href='../src/fs2/lib.rs.html#44-86' title='goto source code'>[src]</a></span></h1>
<pre class='rust trait'>pub trait FileExt {
fn <a href='#tymethod.duplicate' class='fnname'>duplicate</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="struct" href="https://doc.rust-lang.org/nightly/std/fs/struct.File.html" title="struct std::fs::File">File</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.allocated_size' class='fnname'>allocated_size</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.allocate' class='fnname'>allocate</a>(&amp;self, len: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.lock_shared' class='fnname'>lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.lock_exclusive' class='fnname'>lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.try_lock_shared' class='fnname'>try_lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.try_lock_exclusive' class='fnname'>try_lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
<div class='item-spacer'></div> fn <a href='#tymethod.unlock' class='fnname'>unlock</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;;
}</pre><div class='docblock'><p>Extension trait for <code>std::fs::File</code> which provides allocation, duplication and locking methods.</p>
<h2 id="notes-on-file-locks" class="section-header"><a href="#notes-on-file-locks">Notes on File Locks</a></h2>
<p>This library provides whole-file locks in both shared (read) and exclusive
(read-write) varieties.</p>
<p>File locks are a cross-platform hazard since the file lock APIs exposed by
operating system kernels vary in subtle and not-so-subtle ways.</p>
<p>The API exposed by this library can be safely used across platforms as long
as the following rules are followed:</p>
<ul>
<li>Multiple locks should not be created on an individual <code>File</code> instance
concurrently.</li>
<li>Duplicated files should not be locked without great care.</li>
<li>Files to be locked should be opened with at least read or write
permissions.</li>
<li>File locks may only be relied upon to be advisory.</li>
</ul>
<p>See the tests in <code>lib.rs</code> for cross-platform lock behavior that may be
relied upon; see the tests in <code>unix.rs</code> and <code>windows.rs</code> for examples of
platform-specific behavior. File locks are implemented with
<a href="http://man7.org/linux/man-pages/man2/flock.2.html"><code>flock(2)</code></a> on Unix and
<a href="https://msdn.microsoft.com/en-us/library/windows/desktop/aa365202(v=vs.85).aspx"><code>LockFile</code></a>
on Windows.</p>
</div>
<h2 id='required-methods' class='small-section-header'>
Required Methods<a href='#required-methods' class='anchor'></a>
</h2>
<div class='methods'>
<h3 id='tymethod.duplicate' class='method'><span id='duplicate.v' class='invisible'><code>fn <a href='#tymethod.duplicate' class='fnname'>duplicate</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="struct" href="https://doc.rust-lang.org/nightly/std/fs/struct.File.html" title="struct std::fs::File">File</a>&gt;</code></span></h3><div class='docblock'><p>Returns a duplicate instance of the file.</p>
<p>The returned file will share the same file position as the original
file.</p>
<h1 id="notes" class="section-header"><a href="#notes">Notes</a></h1>
<p>This is implemented with
<a href="http://man7.org/linux/man-pages/man2/dup.2.html"><code>dup(2)</code></a> on Unix and
<a href="https://msdn.microsoft.com/en-us/library/windows/desktop/ms724251(v=vs.85).aspx"><code>DuplicateHandle</code></a>
on Windows.</p>
</div><h3 id='tymethod.allocated_size' class='method'><span id='allocated_size.v' class='invisible'><code>fn <a href='#tymethod.allocated_size' class='fnname'>allocated_size</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>&gt;</code></span></h3><div class='docblock'><p>Returns the amount of physical space allocated for a file.</p>
</div><h3 id='tymethod.allocate' class='method'><span id='allocate.v' class='invisible'><code>fn <a href='#tymethod.allocate' class='fnname'>allocate</a>(&amp;self, len: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Ensures that at least <code>len</code> bytes of disk space are allocated for the
file, and the file size is at least <code>len</code> bytes. After a successful call
to <code>allocate</code>, subsequent writes to the file within the specified length
are guaranteed not to fail because of lack of disk space.</p>
</div><h3 id='tymethod.lock_shared' class='method'><span id='lock_shared.v' class='invisible'><code>fn <a href='#tymethod.lock_shared' class='fnname'>lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Locks the file for shared usage, blocking if the file is currently
locked exclusively.</p>
</div><h3 id='tymethod.lock_exclusive' class='method'><span id='lock_exclusive.v' class='invisible'><code>fn <a href='#tymethod.lock_exclusive' class='fnname'>lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Locks the file for exclusive usage, blocking if the file is currently
locked.</p>
</div><h3 id='tymethod.try_lock_shared' class='method'><span id='try_lock_shared.v' class='invisible'><code>fn <a href='#tymethod.try_lock_shared' class='fnname'>try_lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Locks the file for shared usage, or returns a an error if the file is
currently locked (see <code>lock_contended_error</code>).</p>
</div><h3 id='tymethod.try_lock_exclusive' class='method'><span id='try_lock_exclusive.v' class='invisible'><code>fn <a href='#tymethod.try_lock_exclusive' class='fnname'>try_lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Locks the file for shared usage, or returns a an error if the file is
currently locked (see <code>lock_contended_error</code>).</p>
</div><h3 id='tymethod.unlock' class='method'><span id='unlock.v' class='invisible'><code>fn <a href='#tymethod.unlock' class='fnname'>unlock</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span></h3><div class='docblock'><p>Unlocks the file.</p>
</div></div>
<h2 id='foreign-impls' class='small-section-header'>
Implementations on Foreign Types<a href='#foreign-impls' class='anchor'></a>
</h2>
<h3 id='impl-FileExt' class='impl'><span class='in-band'><code>impl <a class="trait" href="../fs2/trait.FileExt.html" title="trait fs2::FileExt">FileExt</a> for <a class="struct" href="https://doc.rust-lang.org/nightly/std/fs/struct.File.html" title="struct std::fs::File">File</a></code><a href='#impl-FileExt' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#88-113' title='goto source code'>[src]</a></span></h3>
<span class='docblock autohide'><div class='impl-items'><h4 id='method.duplicate' class="method"><span id='duplicate.v-1' class='invisible'><code>fn <a href='#method.duplicate' class='fnname'>duplicate</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="struct" href="https://doc.rust-lang.org/nightly/std/fs/struct.File.html" title="struct std::fs::File">File</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#89-91' title='goto source code'>[src]</a></span></h4>
<h4 id='method.allocated_size' class="method"><span id='allocated_size.v-1' class='invisible'><code>fn <a href='#method.allocated_size' class='fnname'>allocated_size</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#92-94' title='goto source code'>[src]</a></span></h4>
<h4 id='method.allocate' class="method"><span id='allocate.v-1' class='invisible'><code>fn <a href='#method.allocate' class='fnname'>allocate</a>(&amp;self, len: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#95-97' title='goto source code'>[src]</a></span></h4>
<h4 id='method.lock_shared' class="method"><span id='lock_shared.v-1' class='invisible'><code>fn <a href='#method.lock_shared' class='fnname'>lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#98-100' title='goto source code'>[src]</a></span></h4>
<h4 id='method.lock_exclusive' class="method"><span id='lock_exclusive.v-1' class='invisible'><code>fn <a href='#method.lock_exclusive' class='fnname'>lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#101-103' title='goto source code'>[src]</a></span></h4>
<h4 id='method.try_lock_shared' class="method"><span id='try_lock_shared.v-1' class='invisible'><code>fn <a href='#method.try_lock_shared' class='fnname'>try_lock_shared</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#104-106' title='goto source code'>[src]</a></span></h4>
<h4 id='method.try_lock_exclusive' class="method"><span id='try_lock_exclusive.v-1' class='invisible'><code>fn <a href='#method.try_lock_exclusive' class='fnname'>try_lock_exclusive</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#107-109' title='goto source code'>[src]</a></span></h4>
<h4 id='method.unlock' class="method"><span id='unlock.v-1' class='invisible'><code>fn <a href='#method.unlock' class='fnname'>unlock</a>(&amp;self) -&gt; <a class="type" href="https://doc.rust-lang.org/nightly/std/io/error/type.Result.html" title="type std::io::error::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/fs2/lib.rs.html#110-112' title='goto source code'>[src]</a></span></h4>
</div></span>
<h2 id='implementors' class='small-section-header'>
Implementors<a href='#implementors' class='anchor'></a>
</h2>
<ul class='item-list' id='implementors-list'>
</ul><script type="text/javascript" async
src="../implementors/fs2/trait.FileExt.js">
</script></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>&#9166;</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 = "fs2";
</script>
<script src="../main.js"></script>
<script defer src="../search-index.js"></script>
</body>
</html>