| |
| |
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="utf-8"> |
| <meta http-equiv="X-UA-Compatible" content="IE=edge"> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> |
| |
| |
| |
| |
| <title>fsutil_read_file — Apache Mynewt latest documentation</title> |
| |
| |
| |
| |
| <link rel="shortcut icon" href="../../../../_static/mynewt-logo-only-newt32x32.png"/> |
| |
| |
| |
| |
| <link rel="stylesheet" href="../../../../_static/css/theme.css" type="text/css" /> |
| |
| |
| <link rel="stylesheet" href="../../../../_static/css/sphinx_theme.css" type="text/css" /> |
| |
| <link rel="stylesheet" href="../../../../_static/css/bootstrap-3.0.3.min.css" type="text/css" /> |
| |
| <link rel="stylesheet" href="../../../../_static/css/v2.css" type="text/css" /> |
| |
| <link rel="stylesheet" href="../../../../_static/css/custom.css" type="text/css" /> |
| |
| <link rel="stylesheet" href="../../../../_static/css/restructuredtext.css" type="text/css" /> |
| |
| |
| |
| |
| <link rel="stylesheet" href="../../../../_static/css/overrides.css" type="text/css" /> |
| <link rel="index" title="Index" |
| href="../../../../genindex.html"/> |
| <link rel="search" title="Search" href="../../../../search.html"/> |
| <link rel="top" title="Apache Mynewt latest documentation" href="../../../../index.html"/> |
| |
| |
| <script src="../../../../_static/js/modernizr.min.js"></script> |
| |
| |
| <script> |
| (function(i, s, o, g, r, a, m) { |
| i["GoogleAnalyticsObject"] = r; |
| (i[r] = |
| i[r] || |
| function() { |
| (i[r].q = i[r].q || []).push(arguments); |
| }), |
| (i[r].l = 1 * new Date()); |
| (a = s.createElement(o)), (m = s.getElementsByTagName(o)[0]); |
| a.async = 1; |
| a.src = g; |
| m.parentNode.insertBefore(a, m); |
| })(window, document, "script", "//www.google-analytics.com/analytics.js", "ga"); |
| |
| ga("create", "UA-72162311-1", "auto"); |
| ga("send", "pageview"); |
| </script> |
| |
| |
| </head> |
| |
| <body class="not-front page-documentation" role="document" > |
| <div id="wrapper"> |
| <div class="container"> |
| <div id="banner" class="row v2-main-banner"> |
| <a class="logo-cell" href="/"> |
| <img class="logo" src="../../../../_static/img/logo.png"> |
| </a> |
| <div class="tagline-cell"> |
| <h4 class="tagline">An OS to build, deploy and securely manage billions of devices</h4> |
| </div> |
| <div class="news-cell"> |
| <div class="well"> |
| <h4>Latest News:</h4> <a href="/download">Apache Mynewt 1.12.0, Apache NimBLE 1.7.0 </a> released April 4, 2024) |
| </div> |
| </div> |
| </div> |
| </div> |
| |
| <header> |
| <nav id="navbar" class="navbar navbar-inverse" role="navigation"> |
| <div class="container"> |
| <!-- Collapsed navigation --> |
| <div class="navbar-header"> |
| <!-- Expander button --> |
| <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse"> |
| <span class="sr-only">Toggle navigation</span> |
| <span class="icon-bar"></span> |
| <span class="icon-bar"></span> |
| <span class="icon-bar"></span> |
| </button> |
| |
| </div> |
| |
| <!-- Expanded navigation --> |
| <div class="navbar-collapse collapse"> |
| <!-- Main navigation --> |
| <ul class="nav navbar-nav navbar-right"> |
| <li> |
| <a href="/"><i class="fa fa-home" style="font-size: larger;"></i></a> |
| </li> |
| <li class="important"> |
| <a href="/quick-start/">Quick Start</a> |
| </li> |
| <li> |
| <a href="/about/">About</a> |
| </li> |
| <li> |
| <a href="/talks/">Talks</a> |
| </li> |
| <li class="active"> |
| <a href="/documentation/">Documentation</a> |
| </li> |
| <li> |
| <a href="/download/">Download</a> |
| </li> |
| <li> |
| <a href="/community/">Community</a> |
| </li> |
| <li> |
| <a href="/events/">Events</a> |
| </li> |
| </ul> |
| |
| <!-- Search, Navigation and Repo links --> |
| <ul class="nav navbar-nav navbar-right"> |
| |
| </ul> |
| </div> |
| </div> |
| </nav> |
| </header> |
| <!-- STARTS MAIN CONTENT --> |
| <div id="main-content"> |
| |
| |
| |
| |
| |
| |
| <div id="breadcrumb"> |
| <div class="container"> |
| <a href="/documentation/">Docs</a> / |
| |
| fsutil_read_file |
| |
| <div class="sourcelink"> |
| <a href="https://github.com/apache/mynewt-core/edit/master/docs/os/modules/fs/fs/fsutil_read_file.rst" class="icon icon-github" |
| rel="nofollow"> Edit on GitHub</a> |
| </div> |
| </div> |
| </div> |
| <!-- STARTS CONTAINER --> |
| <div class="container"> |
| <!-- STARTS .content --> |
| <div id="content" class="row"> |
| |
| <!-- STARTS .container-sidebar --> |
| <div class="container-sidebar col-xs-12 col-sm-3"> |
| <div id="docSidebar" class="sticky-container"> |
| <div role="search" class="sphinx-search"> |
| <form id="rtd-search-form" class="wy-form" action="../../../../search.html" method="get"> |
| <input type="text" name="q" placeholder="Search documentation" class="search-documentation" /> |
| <input type="hidden" name="check_keywords" value="yes" /> |
| <input type="hidden" name="area" value="default" /> |
| </form> |
| </div> |
| <!-- Note: only works when deployed --> |
| <select class="form-control" onchange="if (this.value) window.location.href=this.value"> |
| <option value="/latest" selected> |
| Version: latest |
| </option> |
| <option value="/v1_12_0" > |
| Version: 1.12.0 |
| </option> |
| <option value="/v1_11_0" > |
| Version: 1.11.0 |
| </option> |
| <option value="/v1_10_0" > |
| Version: 1.10.0 |
| </option> |
| <option value="/v1_9_0" > |
| Version: 1.9.0 |
| </option> |
| <option value="/v1_8_0" > |
| Version: 1.8.0 |
| </option> |
| <option value="/v1_7_0" > |
| Version: 1.7.0 |
| </option> |
| <option value="/v1_6_0" > |
| Version: 1.6.0 |
| </option> |
| <option value="/v1_5_0" > |
| Version: 1.5.0 |
| </option> |
| <option value="/v1_4_0" selected="selected" > |
| Version: 1.4.0 |
| </option> |
| <option value="/v1_3_0/os/introduction" > |
| Version: 1.3.0 |
| </option> |
| <option value="/v1_2_0/os/introduction" > |
| Version: 1.2.0 |
| </option> |
| <option value="/v1_1_0/os/introduction" > |
| Version: 1.1.0 |
| </option> |
| <option value="/v1_0_0/os/introduction" > |
| Version: 1.0.0 |
| </option> |
| <option value="/v0_9_0/os/introduction" > |
| Version: 0.9.0 |
| </option> |
| </select> |
| <div class="region region-sidebar"> |
| <div class="docs-menu"> |
| |
| |
| |
| <ul> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../index.html">Introduction</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../get_started/index.html">Setup & Get Started</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../concepts.html">Concepts</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../tutorials/tutorials.html">Tutorials</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../external_links.html">Third-party Resources</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../os_user_guide.html">OS User Guide</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../network/index.html">BLE User Guide</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../newt/index.html">Newt Tool Guide</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../newtmgr/index.html">Newt Manager Guide</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../mynewt_faq/index.html">Mynewt FAQ</a></li> |
| <li class="toctree-l1"><a class="reference internal" href="../../../../misc/index.html">Appendix</a></li> |
| </ul> |
| |
| |
| |
| </div> |
| </div> |
| </div> |
| <!-- ENDS STICKY CONTAINER --> |
| </div> |
| <!-- ENDS .container-sidebar --> |
| |
| <div class="col-xs-12 col-sm-9"> |
| |
| <div class="alert alert-warning"> |
| <p> |
| Version 1.4.0 is not the most recent version of the |
| Apache Mynewt documentation. Click <a href="/latest">here</a> to |
| read the latest version. |
| </p> |
| </div> |
| |
| |
| |
| <div class=""> |
| <div class="rst-content"> |
| <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article"> |
| <div itemprop="articleBody"> |
| |
| <div class="section" id="fsutil-read-file"> |
| <h1>fsutil_read_file<a class="headerlink" href="#fsutil-read-file" title="Permalink to this headline">¶</a></h1> |
| <div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="kt">int</span><span class="w"> </span><span class="n">fsutil_read_file</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="kt">char</span><span class="w"> </span><span class="o">*</span><span class="n">path</span><span class="p">,</span><span class="w"> </span><span class="kt">uint32_t</span><span class="w"> </span><span class="n">offset</span><span class="p">,</span><span class="w"> </span><span class="kt">uint32_t</span><span class="w"> </span><span class="n">len</span><span class="p">,</span> |
| <span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="o">*</span><span class="n">dst</span><span class="p">,</span><span class="w"> </span><span class="kt">uint32_t</span><span class="w"> </span><span class="o">*</span><span class="n">out_len</span><span class="p">)</span> |
| </pre></div> |
| </div> |
| <p>Calls fs_open(), fs_read(), and fs_close() to open a file at the |
| specified path, retrieve data from the file starting from the specified |
| offset, and close the file and invalidate the file handle.</p> |
| <div class="section" id="arguments"> |
| <h2>Arguments<a class="headerlink" href="#arguments" title="Permalink to this headline">¶</a></h2> |
| <table class="docutils align-default"> |
| <colgroup> |
| <col style="width: 47%" /> |
| <col style="width: 53%" /> |
| </colgroup> |
| <thead> |
| <tr class="row-odd"><th class="head"><p><em>Argument</em></p></th> |
| <th class="head"><p><em>Description</em></p></th> |
| </tr> |
| </thead> |
| <tbody> |
| <tr class="row-even"><td><p>path</p></td> |
| <td><p>Pointer to the |
| directory |
| entry to query</p></td> |
| </tr> |
| <tr class="row-odd"><td><p>offset</p></td> |
| <td><p>Position of |
| the file’s |
| read pointer</p></td> |
| </tr> |
| <tr class="row-even"><td><p>len</p></td> |
| <td><p>Number of |
| bytes to |
| attempt to |
| read</p></td> |
| </tr> |
| <tr class="row-odd"><td><p>dst</p></td> |
| <td><p>Destination |
| buffer to read |
| into</p></td> |
| </tr> |
| <tr class="row-even"><td><p>out_len</p></td> |
| <td><p>On success, |
| the number of |
| bytes actually |
| read gets |
| written here. |
| Pass null if |
| you don’t |
| care.</p></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="returned-values"> |
| <h2>Returned values<a class="headerlink" href="#returned-values" title="Permalink to this headline">¶</a></h2> |
| <ul class="simple"> |
| <li><p>0 on success</p></li> |
| <li><p><a class="reference external" href="fs_return_codes.html">FS error code</a> on failure</p></li> |
| </ul> |
| </div> |
| <div class="section" id="notes"> |
| <h2>Notes<a class="headerlink" href="#notes" title="Permalink to this headline">¶</a></h2> |
| <p>This is a convenience function. It is useful when the amount of data to |
| be read from the file is small (i.e., all the data read can easily fit |
| in a single buffer).</p> |
| </div> |
| <div class="section" id="header-file"> |
| <h2>Header file<a class="headerlink" href="#header-file" title="Permalink to this headline">¶</a></h2> |
| <div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="cp">#include</span><span class="w"> </span><span class="cpf">"fs/fs.h"</span> |
| </pre></div> |
| </div> |
| </div> |
| <div class="section" id="example"> |
| <h2>Example<a class="headerlink" href="#example" title="Permalink to this headline">¶</a></h2> |
| <p>This example demonstrates reading a small text file in its entirety and |
| printing its contents to the console.</p> |
| <div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="kt">int</span> |
| <span class="nf">print_status</span><span class="p">(</span><span class="kt">void</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="kt">uint32_t</span><span class="w"> </span><span class="n">bytes_read</span><span class="p">;</span> |
| <span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">buf</span><span class="p">[</span><span class="mi">16</span><span class="p">];</span> |
| <span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">rc</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="cm">/* Read up to 15 bytes from the start of the file. */</span> |
| <span class="w"> </span><span class="n">rc</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">fsutil_read_file</span><span class="p">(</span><span class="s">"/cfg/status.txt"</span><span class="p">,</span><span class="w"> </span><span class="mi">0</span><span class="p">,</span><span class="w"> </span><span class="k">sizeof</span><span class="w"> </span><span class="n">buf</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="n">buf</span><span class="p">,</span> |
| <span class="w"> </span><span class="o">&</span><span class="n">bytes_read</span><span class="p">);</span> |
| <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">rc</span><span class="w"> </span><span class="o">!=</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">-1</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="cm">/* Null-terminate the string just read. */</span> |
| <span class="w"> </span><span class="n">buf</span><span class="p">[</span><span class="n">bytes_read</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="sc">'\0'</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="cm">/* Print the file contents to the console. */</span> |
| <span class="w"> </span><span class="n">console_printf</span><span class="p">(</span><span class="s">"%s</span><span class="se">\n</span><span class="s">"</span><span class="p">,</span><span class="w"> </span><span class="n">buf</span><span class="p">);</span> |
| |
| <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span> |
| <span class="p">}</span> |
| </pre></div> |
| </div> |
| </div> |
| </div> |
| |
| |
| </div> |
| </div> |
| |
| </div> |
| </div> |
| </div> |
| <!-- ENDS CONTENT SECTION --> |
| </div> |
| <!-- ENDS .content --> |
| </div> |
| </div> |
| <footer> |
| <div class="container"> |
| <div class="row"> |
| <div class="col-xs-12"> |
| |
| <p class="copyright">Apache Mynewt is available under Apache License, version 2.0.</p> |
| |
| </div> |
| <div class="col-xs-12"> |
| <div class="logos"> |
| <img src="../../../../_static/img/asf_logo_wide_small.png" alt="Apache" title="Apache"> |
| <small class="footnote"> |
| Apache Mynewt, Mynewt, Apache, the Apache feather logo, and the Apache Mynewt project logo are either |
| registered trademarks or trademarks of the Apache Software Foundation in the United States and other countries. |
| </small> |
| <a href=""> |
| <img src="../../../../_static/img/add_to_slack.png" alt="Slack Icon" title="Join our Slack Community" /> |
| </a> |
| </div> |
| </div> |
| </div> |
| </div> |
| </footer> |
| </div> |
| <!-- ENDS #wrapper --> |
| |
| |
| |
| <script type="text/javascript"> |
| var DOCUMENTATION_OPTIONS = { |
| URL_ROOT:'../../../../', |
| VERSION:'latest', |
| COLLAPSE_INDEX:false, |
| FILE_SUFFIX:'.html', |
| HAS_SOURCE: true, |
| SOURCELINK_SUFFIX: '.txt', |
| LINK_SUFFIX: '.html' |
| }; |
| </script> |
| <script type="text/javascript" src="../../../../_static/jquery.js"></script> |
| <script type="text/javascript" src="../../../../_static/underscore.js"></script> |
| <script type="text/javascript" src="../../../../_static/doctools.js"></script> |
| <script type="text/javascript" src="../../../../_static/js/bootstrap-3.0.3.min.js"></script> |
| <script type="text/javascript" src="../../../../_static/js/affix.js"></script> |
| <script type="text/javascript" src="../../../../_static/js/main.js"></script> |
| |
| |
| |
| </body> |
| </html> |