xplr/en/environment-variables-and-pipes.html
2022-04-06 09:26:30 +00:00

270 lines
20 KiB
HTML

<!DOCTYPE HTML>
<html lang="en" class="sidebar-visible no-js dark">
<head>
<!-- Book generated using mdBook -->
<meta charset="UTF-8">
<title>Environment Variables and Pipes - xplr book</title>
<!-- Custom HTML head -->
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<meta name="description" content="A hackable, minimal, fast TUI file explorer">
<meta name="viewport" content="width=device-width, initial-scale=1">
<meta name="theme-color" content="#ffffff" />
<link rel="icon" href="favicon.svg">
<link rel="shortcut icon" href="favicon.png">
<link rel="stylesheet" href="css/variables.css">
<link rel="stylesheet" href="css/general.css">
<link rel="stylesheet" href="css/chrome.css">
<link rel="stylesheet" href="css/print.css" media="print">
<!-- Fonts -->
<link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
<link rel="stylesheet" href="fonts/fonts.css">
<!-- Highlight.js Stylesheets -->
<link rel="stylesheet" href="highlight.css">
<link rel="stylesheet" href="tomorrow-night.css">
<link rel="stylesheet" href="ayu-highlight.css">
<!-- Custom theme stylesheets -->
</head>
<body>
<!-- Provide site root to javascript -->
<script type="text/javascript">
var path_to_root = "";
var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "coal" : "dark";
</script>
<!-- Work around some values being stored in localStorage wrapped in quotes -->
<script type="text/javascript">
try {
var theme = localStorage.getItem('mdbook-theme');
var sidebar = localStorage.getItem('mdbook-sidebar');
if (theme.startsWith('"') && theme.endsWith('"')) {
localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
}
if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
}
} catch (e) { }
</script>
<!-- Set the theme before any content is loaded, prevents flash -->
<script type="text/javascript">
var theme;
try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
if (theme === null || theme === undefined) { theme = default_theme; }
var html = document.querySelector('html');
html.classList.remove('no-js')
html.classList.remove('dark')
html.classList.add(theme);
html.classList.add('js');
</script>
<!-- Hide / unhide sidebar before it is displayed -->
<script type="text/javascript">
var html = document.querySelector('html');
var sidebar = 'hidden';
if (document.body.clientWidth >= 1080) {
try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
sidebar = sidebar || 'visible';
}
html.classList.remove('sidebar-visible');
html.classList.add("sidebar-" + sidebar);
</script>
<nav id="sidebar" class="sidebar" aria-label="Table of contents">
<div class="sidebar-scrollbox">
<ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="quickstart.html"><strong aria-hidden="true">2.</strong> Quickstart</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="install.html"><strong aria-hidden="true">2.1.</strong> Install</a></li><li class="chapter-item expanded "><a href="post-install.html"><strong aria-hidden="true">2.2.</strong> Post Install</a></li></ol></li><li class="chapter-item expanded "><a href="configuration.html"><strong aria-hidden="true">3.</strong> Configuration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="general-config.html"><strong aria-hidden="true">3.1.</strong> General</a></li><li class="chapter-item expanded "><a href="node_types.html"><strong aria-hidden="true">3.2.</strong> Node Types</a></li><li class="chapter-item expanded "><a href="layouts.html"><strong aria-hidden="true">3.3.</strong> Layouts</a></li><li class="chapter-item expanded "><a href="modes.html"><strong aria-hidden="true">3.4.</strong> Modes</a></li></ol></li><li class="chapter-item expanded "><a href="concept.html"><strong aria-hidden="true">4.</strong> Concept</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="key-bindings.html"><strong aria-hidden="true">4.1.</strong> Key Bindings</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="configure-key-bindings.html"><strong aria-hidden="true">4.1.1.</strong> Configure Key Bindings</a></li><li class="chapter-item expanded "><a href="default-key-bindings.html"><strong aria-hidden="true">4.1.2.</strong> Default Key Bindings</a></li><li class="chapter-item expanded "><a href="debug-key-bindings.html"><strong aria-hidden="true">4.1.3.</strong> Debug Key Bindings</a></li></ol></li><li class="chapter-item expanded "><a href="node-type.html"><strong aria-hidden="true">4.2.</strong> Node Type</a></li><li class="chapter-item expanded "><a href="layout.html"><strong aria-hidden="true">4.3.</strong> Layout</a></li><li class="chapter-item expanded "><a href="mode.html"><strong aria-hidden="true">4.4.</strong> Mode</a></li><li class="chapter-item expanded "><a href="message.html"><strong aria-hidden="true">4.5.</strong> Message</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="messages.html"><strong aria-hidden="true">4.5.1.</strong> Full List of Messages</a></li><li class="chapter-item expanded "><a href="input-operation.html"><strong aria-hidden="true">4.5.2.</strong> Input Operation</a></li></ol></li><li class="chapter-item expanded "><a href="borders.html"><strong aria-hidden="true">4.6.</strong> Borders</a></li><li class="chapter-item expanded "><a href="style.html"><strong aria-hidden="true">4.7.</strong> Style</a></li><li class="chapter-item expanded "><a href="sorting.html"><strong aria-hidden="true">4.8.</strong> Sorting</a></li><li class="chapter-item expanded "><a href="filtering.html"><strong aria-hidden="true">4.9.</strong> Filtering</a></li><li class="chapter-item expanded "><a href="column-renderer.html"><strong aria-hidden="true">4.10.</strong> Column Renderer</a></li><li class="chapter-item expanded "><a href="lua-function-calls.html"><strong aria-hidden="true">4.11.</strong> Lua Function Calls</a></li><li class="chapter-item expanded "><a href="environment-variables-and-pipes.html" class="active"><strong aria-hidden="true">4.12.</strong> Environment Variables and Pipes</a></li></ol></li><li class="chapter-item expanded "><a href="awesome-hacks.html"><strong aria-hidden="true">5.</strong> Awesome Hacks</a></li><li class="chapter-item expanded "><a href="plugin.html"><strong aria-hidden="true">6.</strong> Plugin</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="installing-plugins.html"><strong aria-hidden="true">6.1.</strong> Installing Plugins</a></li><li class="chapter-item expanded "><a href="writing-plugins.html"><strong aria-hidden="true">6.2.</strong> Writing Plugins</a></li><li class="chapter-item expanded "><a href="awesome-plugins.html"><strong aria-hidden="true">6.3.</strong> Awesome Plugins</a></li></ol></li><li class="chapter-item expanded "><a href="integration.html"><strong aria-hidden="true">7.</strong> Integration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="awesome-integrations.html"><strong aria-hidden="true">7.1.</strong> Awesome Integrations</a></li></ol></li><li class="chapter-item expanded "><a href="todo.html"><strong aria-hidden="true">8.</strong> TODO</a></li><li class="chapter-item expanded "><a href="alternatives.html"><strong aria-hidden="true">9.</strong> Alternatives</a></li><li class="chapter-item expanded "><a href="upgrade-guide.html"><strong aria-hidden="true">10.</strong> Upgrade Guide</a></li><li class="chapter-item expanded "><a href="community.html"><strong aria-hidden="true">11.</strong> Community</a></li><li class="chapter-item expanded "><a href="contribute.html"><strong aria-hidden="true">12.</strong> Contribute</a></li></ol>
</div>
<div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
</nav>
<div id="page-wrapper" class="page-wrapper">
<div class="page">
<div id="menu-bar-hover-placeholder"></div>
<div id="menu-bar" class="menu-bar sticky bordered">
<div class="left-buttons">
<button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
<i class="fa fa-bars"></i>
</button>
<button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
<i class="fa fa-paint-brush"></i>
</button>
<ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
<li role="none"><button role="menuitem" class="theme" id="light">Light</button></li>
<li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
<li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
<li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
<li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
</ul>
<button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
<i class="fa fa-search"></i>
</button>
</div>
<h1 class="menu-title">xplr book</h1>
<div class="right-buttons">
<a href="print.html" title="Print this book" aria-label="Print this book">
<i id="print-button" class="fa fa-print"></i>
</a>
<a href="https://github.com/sayanarijit/xplr" title="Git repository" aria-label="Git repository">
<i id="git-repository-button" class="fa fa-github"></i>
</a>
<a href="https://github.com/sayanarijit/xplr/edit/main/docs/en/src/environment-variables-and-pipes.md" title="Suggest an edit" aria-label="Suggest an edit">
<i id="git-edit-button" class="fa fa-edit"></i>
</a>
</div>
</div>
<div id="search-wrapper" class="hidden">
<form id="searchbar-outer" class="searchbar-outer">
<input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
</form>
<div id="searchresults-outer" class="searchresults-outer hidden">
<div id="searchresults-header" class="searchresults-header"></div>
<ul id="searchresults">
</ul>
</div>
</div>
<!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
<script type="text/javascript">
document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
});
</script>
<div id="content" class="content">
<main>
<h1 id="environment-variables-and-pipes"><a class="header" href="#environment-variables-and-pipes">Environment Variables and Pipes</a></h1>
<p>Alternative to <code>CallLua</code>, <code>CallLuaSilently</code> messages that call Lua functions,
there are <code>Call</code>, <code>CallSilently</code>, <code>BashExec</code>, <code>BashExecSilently</code> messages
that call shell commands.</p>
<p>However, unlike the Lua functions, these shell commands have to read the useful
information and send messages via environment variables and temporary files
called &quot;pipe&quot;s. These environment variables and files are only available when
a command is being executed.</p>
<p>Visit the <a href="configure-key-bindings.html#tutorial-adding-a-new-mode"><strong>fzf integration tutorial</strong></a>
for example.</p>
<h3 id="environment-variables"><a class="header" href="#environment-variables">Environment variables</a></h3>
<p>To see the environment variables, invoke the shell by typing <code>:!</code> in default
mode and run the following command:</p>
<pre><code>env | grep ^XPLR_
</code></pre>
<p>You will see something like:</p>
<pre><code>XPLR_FOCUS_INDEX=0
XPLR_MODE=action to
XPLR_PIPE_SELECTION_OUT=/run/user/1000/xplr/session/122278/pipe/selection_out
XPLR_INPUT_BUFFER=
XPLR_PIPE_GLOBAL_HELP_MENU_OUT=/run/user/1000/xplr/session/122278/pipe/global_help_menu_out
XPLR_PID=122278
XPLR_PIPE_MSG_IN=/run/user/1000/xplr/session/122278/pipe/msg_in
XPLR_PIPE_LOGS_OUT=/run/user/1000/xplr/session/122278/pipe/logs_out
XPLR_PIPE_RESULT_OUT=/run/user/1000/xplr/session/122278/pipe/result_out
XPLR_PIPE_HISTORY_OUT=/run/user/1000/xplr/session/122278/pipe/history_out
XPLR_FOCUS_PATH=/home/sayanarijit/Documents/GitHub/xplr/docs/en/book
XPLR_SESSION_PATH=/run/user/1000/xplr/session/122278
XPLR_APP_VERSION=0.14.3
XPLR_PIPE_DIRECTORY_NODES_OUT=/run/user/1000/xplr/session/122278/pipe/directory_nodes_out
</code></pre>
<p>The environment variables starting with <code>XPLR_PIPE_</code> are the temporary files
called &quot;pipe&quot;s.</p>
<h4 id="input-pipe"><a class="header" href="#input-pipe">Input pipe</a></h4>
<p>Current there is only one input pipe.</p>
<ul>
<li><a href="#xplr_pipe_msg_in">XPLR_PIPE_MSG_IN</a></li>
</ul>
<h4 id="output-pipes"><a class="header" href="#output-pipes">Output pipes</a></h4>
<p><code>XPLR_PIPE_*_OUT</code> are the output pipes that contain data which cannot be
exposed directly via environment variables, like multi-line string.</p>
<ul>
<li><a href="#xplr_pipe_selection_out">XPLR_PIPE_SELECTION_OUT</a></li>
<li><a href="#xplr_pipe_global_help_menu_out">XPLR_PIPE_GLOBAL_HELP_MENU_OUT</a></li>
<li><a href="#xplr_pipe_logs_out">XPLR_PIPE_LOGS_OUT</a></li>
<li><a href="#xplr_pipe_result_out">XPLR_PIPE_RESULT_OUT</a></li>
<li><a href="#xplr_pipe_history_out">XPLR_PIPE_HISTORY_OUT</a></li>
<li><a href="#xplr_pipe_directory_nodes_out">XPLR_PIPE_DIRECTORY_NODES_OUT</a></li>
</ul>
<h4 id="xplr_pipe_msg_in"><a class="header" href="#xplr_pipe_msg_in">XPLR_PIPE_MSG_IN</a></h4>
<p>Append new-line delimited messages to this pipe in <a href="https://www.yaml.org">YAML</a>
(or <a href="https://www.json.org">JSON</a>) syntax. These messages will be read and
handled by xplr after the command execution.</p>
<h4 id="xplr_pipe_selection_out"><a class="header" href="#xplr_pipe_selection_out">XPLR_PIPE_SELECTION_OUT</a></h4>
<p>New-line delimited list of selected paths.</p>
<h4 id="xplr_pipe_global_help_menu_out"><a class="header" href="#xplr_pipe_global_help_menu_out">XPLR_PIPE_GLOBAL_HELP_MENU_OUT</a></h4>
<p>The full help menu.</p>
<h4 id="xplr_pipe_logs_out"><a class="header" href="#xplr_pipe_logs_out">XPLR_PIPE_LOGS_OUT</a></h4>
<p>New-line delimited list of logs.</p>
<h4 id="xplr_pipe_result_out"><a class="header" href="#xplr_pipe_result_out">XPLR_PIPE_RESULT_OUT</a></h4>
<p>New-line delimited result (selected paths if any, else the focused path)</p>
<h4 id="xplr_pipe_history_out"><a class="header" href="#xplr_pipe_history_out">XPLR_PIPE_HISTORY_OUT</a></h4>
<p>New-line delimited list of last visited paths (similar to jump list in vim).</p>
<h4 id="xplr_pipe_directory_nodes_out"><a class="header" href="#xplr_pipe_directory_nodes_out">XPLR_PIPE_DIRECTORY_NODES_OUT</a></h4>
<p>New-line delimited list of paths, filtered and sorted as displayed in the
<a href="layout.html#table">files table</a>.</p>
<h3 id="example-using-environment-variables-and-pipes"><a class="header" href="#example-using-environment-variables-and-pipes">Example: Using Environment Variables and Pipes</a></h3>
<pre><code class="language-lua">xplr.config.modes.builtin.default.key_bindings.on_key.space = {
help = &quot;ask name and greet&quot;,
messages = {
{
BashExec = [===[
echo &quot;What's your name?&quot;
read name
greeting=&quot;Hello $name!&quot;
message=&quot;$greeting You are inside $PWD&quot;
echo LogSuccess: '&quot;'$message'&quot;' &gt;&gt; &quot;${XPLR_PIPE_MSG_IN:?}&quot;
]===]
}
}
}
-- Now, when you press &quot;space&quot; in default mode, you will be prompted for your
-- name. Enter your name to receive a nice greeting and to know your location.
</code></pre>
</main>
<nav class="nav-wrapper" aria-label="Page navigation">
<!-- Mobile navigation buttons -->
<a rel="prev" href="lua-function-calls.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
<i class="fa fa-angle-left"></i>
</a>
<a rel="next" href="awesome-hacks.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
<i class="fa fa-angle-right"></i>
</a>
<div style="clear: both"></div>
</nav>
</div>
</div>
<nav class="nav-wide-wrapper" aria-label="Page navigation">
<a rel="prev" href="lua-function-calls.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
<i class="fa fa-angle-left"></i>
</a>
<a rel="next" href="awesome-hacks.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
<i class="fa fa-angle-right"></i>
</a>
</nav>
</div>
<script type="text/javascript">
window.playground_copyable = true;
</script>
<script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
<script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
<script src="searcher.js" type="text/javascript" charset="utf-8"></script>
<script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
<script src="highlight.js" type="text/javascript" charset="utf-8"></script>
<script src="book.js" type="text/javascript" charset="utf-8"></script>
<!-- Custom JS scripts -->
</body>
</html>