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cURL: curl_init , curl_setopt , curl_exec , curl_errno , curl_error , curl_getinfo , curl_close , http_build_query
cURL Constants: CURLOPT_URL, CURLOPT_HEADER, CURLOPT_NOBODY, CURLOPT_HTTPGET, CURLOPT_RETURNTRANSFER
PHP Constants: Most PHP Constants are allowed. Contact PCR if you find one that is not allowed, but would like to use.
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