How can I enable cURL for an installed Ubuntu LAMP stack?

From Install Curl Extension for PHP in Ubuntu:

sudo apt-get install php5-curl

After installing libcurl, you should restart the web server with one of the following commands,

sudo /etc/init.d/apache2 restart

or

sudo service apache2 restart

You only have to install the php5-curl library. You can do this by running

sudo apt-get install php5-curl

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