Hi Nilesh...

I don't expect a difference with 7.15.2 versus 7.15.3, but your tests will
verify that.

CURLOPT_CONNECT_ONLY allows curl to set up the connection, but not perform
any transfer of data. Typically the application then gets the socket by
getting info with the CURLINFO_LASTSOCKET option. After that, the
application performs its own custom transfer.

HTH,

...Karl

>From: Nilesh Subject: Re: Patch for CURLOPT_CONNECT_ONLY
>Date: Wed, 22 Mar 2006 10:35:57 +0530
>
>Thanks Karl !
>
>I think only difference here is curl version I was trying with 7.15.2 and
>you tried with 7.15.3
>
>Let me try the same code again with my test webserver and also check the
>error code at each step.
>
>As you said same curl handle cannot be used for HTTP POST, what is the use
>of CONNECT_ONLY option ?
>May be I am not clear on use of this feature. What I understood and wanted
>to do is as follows,
>
>- With first perform I can check if connection can be established with
>webserver.
>- Only after successfull connection establishment, I can transfer data
>using same curl handle. Ofcourse while doing data transfer, connection may
>go down, that time perform call may fail which is fine.
>
>If not CONNECT_ONLY, what is the way I can get above implemented.
>
>Thanks again for your kind involvement into this.
>
>Thanks,
>Nilesh
>
>Karl M wrote:
>
>>Hi All...
>>
>>I just tried the following code with 7.15.3 and MSVC on an XP Pro machine:
>>
>>#include <fcntl.h>
>>#include <io.h>
>>#include <curl/curl.h>
>>
>>#if LIBCURL_VERSION_NUM < 0x070f02
>>#error "Requires libcurl version 7.15.2 or higher."
>>#endif
>>
>>int main(void) {
>> CURL *curl;
>> CURLcode res;
>> long last_sock=0;
>>
>> char *postthis="moo mooo moo moo";
>>
>> curl = curl_easy_init();
>> if(curl) {
>> curl_easy_setopt(curl, CURLOPT_URL, "http://yahoo.com");
>> curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1);
>>
>> res = curl_easy_perform(curl);
>> res = curl_easy_getinfo(curl, CURLINFO_LASTSOCKET, &last_sock);
>> printf("Return code frm curl_easy_getinfo [%d][%s]\n", res,
>>curl_easy_strerror(res)); // this gives res=43
>> printf("curl_easy_getinfo returned CURLINFO_LASTSOCKET [%ld]\n",
>>last_sock); // last_sock is still 0
>> if(CURLE_OK == res) {
>> printf("curl_easy_getinfo returned CURLINFO_LASTSOCKET [%ld]\n",
>>last_sock);
>> }
>>
>> //curl_easy_setopt(curl, CURLOPT_POSTFIELDS, postthis);
>>
>> /* if we don't provide POSTFIELDSIZE, libcurl will strlen() by
>> itself */
>> //curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, strlen(postthis));
>>
>> //res = curl_easy_perform(curl);
>>
>> /* always cleanup */
>> curl_easy_cleanup(curl);
>> }
>> return 0;
>>}
>>
>>and got the following output:
>>
>>Return code frm curl_easy_getinfo [0][no error]
>>curl_easy_getinfo returned CURLINFO_LASTSOCKET [1940]
>>curl_easy_getinfo returned CURLINFO_LASTSOCKET [1940]
>>
>>I commented out the second half of your code because with
>>CURLOPT_CONNECT_ONLY, I don't think the put could work on the same curl
>>handle.
>>
>>Does your testwebserver exist?
>>
>>Perhaps you could check the error code at each step and see where
>>something first goes wrong.
>>
>>HTH,
>>
>>...Karl
>>
>>>From: Nilesh
>>>Subject: Re: Patch for CURLOPT_CONNECT_ONLY
>>>Date: Fri, 17 Mar 2006 11:55:55 +0530
>>>
>>>
>>>
>>>>>Also if I can get working example for this option, that will be
>>>>>helpful.
>>>>
>>>>
>>>>
>>>>I would like that too, for inclusion in the package.
>>>
>>>
>>>Following is what I am trying to do to test CONNECT_ONLY option. ( I used
>>>simplepost.c example with small modification )
>>>
>>>/int main(void)
>>>{
>>> CURL *curl;
>>> CURLcode res;
>>> long last_sock=0;
>>>
>>> char *postthis="moo mooo moo moo";
>>>
>>> curl = curl_easy_init();
>>> if(curl) {
>>>* curl_easy_setopt(curl, CURLOPT_URL, "http://testwebserver");
>>> curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1);
>>>
>>> res = curl_easy_perform(curl);
>>> res = curl_easy_getinfo(curl, CURLINFO_LASTSOCKET, &last_sock);
>>> printf("Return code frm curl_easy_getinfo [%d][%s]\n", res,
>>>curl_easy_strerror(res)); // this gives res=43
>>> printf("curl_easy_getinfo returned CURLINFO_LASTSOCKET [%ld]\n",
>>>last_sock); // last_sock is still 0
>>> if(CURLE_OK == res)
>>> {
>>> printf("curl_easy_getinfo returned CURLINFO_LASTSOCKET [%ld]\n",
>>>last_sock);
>>> }
>>>*
>>> curl_easy_setopt(curl, CURLOPT_POSTFIELDS, postthis);
>>>
>>> /* if we don't provide POSTFIELDSIZE, libcurl will strlen() by
>>> itself */
>>> curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, strlen(postthis));
>>>
>>> res = curl_easy_perform(curl);
>>>
>>> /* always cleanup */
>>> curl_easy_cleanup(curl);
>>> }
>>> return 0;
>>>}
>>>/
>>>Getting following output:
>>>
>>>*/Return code frm curl_easy_getinfo [43][a libcurl function was given a
>>>bad argument]
>>>curl_easy_getinfo returned CURLINFO_LASTSOCKET [0]
>>>/
>>>*Can you help me to understand how CONNECT_ONLY be used ?
>>>
>>>Thanks,
>>>Nilesh
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
Received on 2006-03-22