Http status code with libcurl?

Solution 1:

http://curl.haxx.se/libcurl/c/curl_easy_getinfo.html

CURLINFO_RESPONSE_CODE

Pass a pointer to a long to receive the last received HTTP or FTP code. This
option was known as CURLINFO_HTTP_CODE in libcurl 7.10.7 and earlier. This 
will be zero if no server response code has been received. Note that a 
proxy's CONNECT response should be read with CURLINFO_HTTP_CONNECTCODE 
and not this. 

curl_code = curl_easy_perform (session);
long http_code = 0;
curl_easy_getinfo (session, CURLINFO_RESPONSE_CODE, &http_code);
if (http_code == 200 && curl_code != CURLE_ABORTED_BY_CALLBACK)
{
         //Succeeded
}
else
{
         //Failed
}

Solution 2:

The other answer is absolutely correct, but I would also like to add that it might not be wise to check the error code by hand, the 200 code is not the only code that signifies success.

I'd recoment using the libcurl option CURLOPT_FAILONERROR that when activated will make libcurl consider 400 and 500 -category statuses a request failure and will not return CURLE_OK from perform.