user4527: I just tried it, but the Arduino IDE crashed, I hope its not related.
I want to declare a datatype like this:
int a = pinMode(pin, OUTPUT);

or something like that, but I'm not sure what datatype the pinMode function uses. I looked on the pinMode documentation page, of the Arduino website, and I see basic usage, but not a more clear definition of the source code for that function.  

user27157: pinMode(pin, Mode); is a void. It doesn't return anything. It simply sets a pin as an OUTPUT or an INPUT.
It says it in the link you posted.

Returns
None

That means that the function doesn't return any value.

4527: <p>I just tried it, but the Arduino IDE crashed, I hope its not related.
I want to declare a datatype like this:</p>

<pre><code>int a = pinMode(pin, OUTPUT);
</code></pre>

<p>or something like that, but I'm not sure what datatype the <code>pinMode</code> function uses. I looked on the <a href="https://www.arduino.cc/en/Reference/pinMode" rel="nofollow noreferrer">pinMode documentation page</a>, of the Arduino website, and I see basic usage, but not a more clear definition of the source code for that function.  </p>
 27157: <p><code>pinMode(pin, Mode);</code> is a <code>void</code>. It doesn't return anything. It simply sets a pin as an <code>OUTPUT</code> or an <code>INPUT</code>.</p>
<p>It says it in the link you posted.</p>
<blockquote>
<p>Returns</p>
<p>None</p>
</blockquote>
<p>That means that the function doesn't return any value.</p>
