php extension fileinfo install in Ubuntu(15.10)
<p>I have tried to install php fileinfo extension in Ubuntu(15.10) and getting errors:</p>

<pre><code>sudo pecl install fileinfo
</code></pre>

<p>Error:</p>

<pre><code>WARNING: "pear/Fileinfo" is deprecated in favor of "channel://php-src/ext/fileinfo/in php sources"
WARNING: channel "pear.php.net" has updated its protocols, use "pecl channel-update pear.php.net" to update
downloading Fileinfo-1.0.4.tgz ...
Starting to download Fileinfo-1.0.4.tgz (5,835 bytes)
.....done: 5,835 bytes
3 source files, building
running: phpize
Cannot find config.m4.
Make sure that you run '/usr/bin/phpize' in the top level source directory of the module

If the command failed with 'phpize: not found' then you need to install php5-dev packageYou can do it by running 'apt-get install php5-dev' as a root userERROR: `phpize' failed
</code></pre>

<p>and then I tried this command:</p>

<pre><code>sudo apt-get install php5-dev
</code></pre>

<p>Output:</p>

<pre><code>Reading package lists... Done
Building dependency tree       
Reading state information... Done
php5-dev is already the newest version.
The following packages were automatically installed and are no longer required:
  linux-headers-4.2.0-16 linux-headers-4.2.0-16-generic
  linux-image-4.2.0-16-generic linux-image-extra-4.2.0-16-generic
  linux-signed-image-4.2.0-16-generic
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
</code></pre>

<p>How I can install php fileinfo extension?
How I can enable this extension?</p>