Unix: Why doesn't env A=42 echo ${A} work?
<p>The <code>env</code> man page says that it'll set the specified environment variables and then run the specified command. Knowing that, I'd expect</p>

<pre><code>env A=42 echo ${A}
</code></pre>

<p>to print <code>42</code>, but it shows nothing instead. What am I doing wrong?</p>