How do I know whether CURL Extension is already installed or not?

[marktan]

I am installing claim listing plugin.
It does not work.
The following message says that I should have CURL Extension installed or allow_url_fopen enabled on my server .

How can I check it?

[Claim Listing Plugin Description

This plugin allows to claim a listing for the user and then assign an ownership for it. Later this user can modify that listing.

NOTE: You should have CURL Extension installed or allow_url_fopen enabled on your server otherwise the plugin won't work.

Thanks for using eSyndiCat Directory Software!]

[Alex B.]

You should ask your hosting company to enable allow_url_fopen to use this plugin

[uk4net]

you can use this functions:

echo ‘cURL is’.(function_exists(‘curl_init’) ? ” : ‘ not’).’ installed’;

or

if ( function_exists(‘curl_version’) == “Enabled” ){ //do something; };