theshell.ch/site/pages/scripts/redirection.html

---
layout: page
category-page: scripts
category-title: Scripting
tags: redirect output input
author: Dario Rasic
title: Redirection
---
<p>
<h3>Output as input</h3>

<p>To redirect a certain output of the command-line we have to use the symbol "&gt;".<br>

In this case, we will use a file named <i>hello.txt</i>, in which we want to insert
a certain output ("Sun" in this case):<br>

<pre>
echo "Sun" > hello.txt
</pre>

So if we print the content of the file in our command-line, the output will be the following:

<pre>
cat hello.txt
    Sun
</pre>

If we want to append a certain output to an existing file,
we just have to use "&gt;&gt;" symbols:</p>

<pre>
cat hello.txt
    Sun
echo "Moon" >> hello.txt
cat hello.txt
    Sun
    Moon
</pre>

<!-- Input redirection text -->
<h3>Input as output</h3>

To redirect an input from a file for a command, the symbol "&lt;" is used.

<pre>
echo < $(cat hello.txt)
    Sun
    Moon
</pre>

This is particularly useful when chaining commands.

<br>

<!-- Chaining command text -->
<h3>Chaining</h3>
<br>
<h1>To be completed</h1>

</p>