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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example: Exit</title>
<link rel=stylesheet href="site.css">
</head>
<script>
onkeydown = (e) => {
if (e.key == "ArrowLeft") {
window.location.href = 'signals';
}
}
</script>
<body>
<div class="example" id="exit">
<h2><a href="./">Go by Example</a>: Exit</h2>
<table>
<tr>
<td class="docs">
<p>Use <code>os.Exit</code> to immediately exit with a given
status.</p>
</td>
<td class="code empty leading">
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<a href="http://play.golang.org/p/b9aYzlENkb__R"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
<pre class="chroma"><span class="kn">package</span> <span class="nx">main</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kn">import</span> <span class="p">(</span>
<span class="s">"fmt"</span>
<span class="s">"os"</span>
<span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kd">func</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p><code>defer</code>s will <em>not</em> be run when using <code>os.Exit</code>, so
this <code>fmt.Println</code> will never be called.</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="k">defer</span> <span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">"!"</span><span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>Exit with status 3.</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">os</span><span class="p">.</span><span class="nf">Exit</span><span class="p">(</span><span class="mi">3</span><span class="p">)</span>
<span class="p">}</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>Note that unlike e.g. C, Go does not use an integer
return value from <code>main</code> to indicate exit status. If
you’d like to exit with a non-zero status you should
use <code>os.Exit</code>.</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<table>
<tr>
<td class="docs">
<p>If you run <code>exit.go</code> using <code>go run</code>, the exit
will be picked up by <code>go</code> and printed.</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="gp">$</span> go run exit.go
<span class="go">exit status 3</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>By building and executing a binary you can see
the status in the terminal.</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="gp">$</span> go build exit.go
<span class="gp">$</span> ./exit
<span class="gp">$</span> echo $?
<span class="go">3</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>Note that the <code>!</code> from our program never got printed.</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="footer">
by <a href="https://markmcgranaghan.com">Mark McGranaghan</a> and <a href="https://eli.thegreenplace.net">Eli Bendersky</a> | <a href="https://github.com/mmcgrana/gobyexample">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
</p>
</div>
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