lessons/bash/ex2.html

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</style><title>ex2</title></head><body><article class="markdown-body"><h1 id="exercises-part-2"><a name="user-content-exercises-part-2" href="#exercises-part-2" class="headeranchor-link" aria-hidden="true"><span class="headeranchor"></span></a>Exercises. Part 2</h1>
<h3 id="consider-the-following-directory-structure"><a name="user-content-consider-the-following-directory-structure" href="#consider-the-following-directory-structure" class="headeranchor-link" aria-hidden="true"><span class="headeranchor"></span></a>Consider the following directory structure</h3>
<p><img alt="" src="img/file-system-exercise.png" /></p>
<h3 id="question"><a name="user-content-question" href="#question" class="headeranchor-link" aria-hidden="true"><span class="headeranchor"></span></a>Question:</h3>
<ul>
<li>What is the output of the closing <code>ls</code> command in the sequence shown below?</li>
</ul>
<pre><code>$ pwd
/home/thesis/data

$ touch proteins.dat

$ ls
proteins.dat

$ mkdir recombine

$ mv proteins.dat recombine

$ cp recombine/proteins.dat ../proteins-saved.dat

$ ls
</code></pre>

<ul>
<li>Suppose that:</li>
</ul>
<pre><code>$ ls -F
analyzed/  fructose.dat    raw/   sucrose.dat
</code></pre>

<ul>
<li>What command(s) (such as <code>rm</code>, <code>mv</code>) could you run so that the commands below will produce the output shown?</li>
</ul>
<pre><code>$ ls
analyzed   raw

$ ls analyzed
fructose.dat    sucrose.dat
</code></pre>

<ul>
<li>What does <code>cp</code> do when given several filenames and a directory name, as in:</li>
</ul>
<pre><code>$ mkdir backup

$ cp thesis/citations.txt thesis/quotations.txt backup
</code></pre>

<ul>
<li>What does <code>cp</code> do when given three or more filenames, as in:</li>
</ul>
<pre><code>$ ls -F    
intro.txt    methods.txt    survey.txt

$ cp intro.txt methods.txt survey.txt
</code></pre>

<ul>
<li>
<p>Why do you think <code>cp</code> behaves differently from <code>mv</code>?</p>
</li>
<li>
<p>The command <code>ls -R</code> lists the contents of directories recursively,<br />
<em>i.e.</em>, lists their sub-directories, sub-sub-directories, and so on<br />
    in alphabetical order at each level. The command <code>ls -t</code> lists things<br />
    by time of last change, with most recently changed files or<br />
    directories first. In what order does <code>ls -R -t</code> display things?</p>
</li>
</ul></article></body></html>