check curl_errno or curl_info first?

[sneakyimp]

I suspect that this section of code is causing one of those fatal errors that terminates your script without so much as a goodbye. Kinda like trying to call a method of a non-object or a nonexistent method of some object.

It also occurs to me that I don't know whether to call curl_info or check curl_errno first? Or under what circumstances curl_exec returns FALSE? Also, is there any way I can check to see if $ch is an open curl resource before calling curl_close to avoid an E_WARNING being thrown? Does checking is_resource($ch) mean that I can be sure to avoid an E_WARNING when I call curl_close?

Any comments on how to improve this code would be most welcome:

			// fetch the remote image
			$ch = curl_init();
			if ($ch === FALSE){
				throw New Exception("curl_init failed");
			}
			MTLog::getInstance()->debug("curl_init complete in slot #" . $this->slot);

		$res_incoming_image_file_handle = fopen($str_incoming_image_file_path, "w+");
		if ($res_incoming_image_file_handle === FALSE){
			throw New Exception("fopen failed for incoming image file");
		}

		MTLog::getInstance()->debug("incoming file handle (" . $str_incoming_image_file_path . ") opened, preparing to set curl options in slot #" . $this->slot);

		curl_setopt($ch, CURLOPT_FILE, $res_incoming_image_file_handle);
		curl_setopt($ch, CURLOPT_URL, $this->cleanUrl($this->pending_img['remote_url']));
		curl_setopt($ch, CURLOPT_FAILONERROR, 1);
		curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 8);
		curl_setopt($ch, CURLOPT_TIMEOUT, 16);
		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
		curl_setopt($ch, CURLOPT_HEADER, 0);

		// didn't work unless i found good cert bundle
		// curl_setopt($ch, CURLOPT_CAINFO, EREP_CA_CERT_BUNDLE_FILE);
		// try this instead
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);

		MTLog::getInstance()->debug("curl options set, preparing to curl-exec in slot #" . $this->slot);

		$curlResult = curl_exec($ch);
		if(!curl_errno($ch)){
			$arr_curl_info = curl_getinfo($ch);
		} else {
			$curl_error_string = "CURL Error #" . curl_errno($ch) . ": " . curl_error($ch);
		}
		curl_close($ch);
		unset($ch);
		fclose($res_incoming_image_file_handle);
		unset($res_incoming_image_file_handle);

		// check for a variety of failure reasons:
		$b_image_success = NULL;
		$str_image_failure_reason = '';
		// curl failure:
		if($curlResult === FALSE){
			$b_image_success = FALSE;
			$str_image_failure_reason = 'curl_exec() returned false. ' . $curl_error_string;
		} else {
			$curlCheck = $this->checkCurlInfo($arr_curl_info, $this->pending_img['remote_url']);
			unset($arr_curl_info);

			if ($curlCheck['result']){
				if (!is_readable($str_incoming_image_file_path) || (filesize($str_incoming_image_file_path) == 0)){
					$b_image_success = FALSE;
					$str_image_failure_reason = 'CURL fetched unreadable or empty file.';
				} else {
					// SUCCESS!
					$b_image_success = TRUE;
				}
			} else {
				$b_image_success = FALSE;
				$str_image_failure_reason = $curlCheck['reason'];
			}
			unset($curlCheck);

		}