atest.sh

[me@webserver /]# php recurlysCurlTest.php
TLS Version Negotiated: TLS 1.0

[me@webserver /]# php recurlysCurlTestModifiedWithCURLOPT_SSLVERSION.php
TLS Version Negotiated: TLS 1.2

recurlysCurlTest.php

<?php
// This example is for testing php with libcurl
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://www.howsmyssl.com/a/check");
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, TRUE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 1);
$response = curl_exec($ch);
curl_close($ch);
list($header, $body) = explode("\r\n\r\n", $response, 2);
$data = json_decode($body, true);
print "TLS Version Negotiated: " . $data['tls_version'] . "\n";

recurlysCurlTestModifiedWithCURLOPT_SSLVERSION.php

<?php
// This example is for testing php with libcurl
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://www.howsmyssl.com/a/check");
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, TRUE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 1);
curl_setopt($ch, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1_2);
$response = curl_exec($ch);
curl_close($ch);
list($header, $body) = explode("\r\n\r\n", $response, 2);
$data = json_decode($body, true);
print "TLS Version Negotiated: " . $data['tls_version'] . "\n";