i do not know what curl will do in this case, but remember, you can look
at whatever env vars you want in your program, and not send curl the
CURLOPT_PROXY* options if they are not there. you can even do better than
that and use a config file or command line switches. thats what i do with
libcurl.

allan

On Mon, Jan 16, 2006, Karl M <karlm30_at_hotmail.com> said:

> Hi All...
>
> If I use libcurl like this
>
>
>
>
> curl_global_init(CURL_GLOBAL_ALL);
> curl = curl_easy_init();
> if(curl) {
> curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, ":");
> curl_easy_setopt(curl, CURLOPT_PROXYAUTH, CURLAUTH_ANYSAFE);
>
> curl_easy_setopt(curl, CURLOPT_URL, url);
>
> curl_easy_setopt(curl, CURLOPT_HTTPPROXYTUNNEL, TRUE);
> curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, TRUE);
>
> res = curl_easy_perform(curl);
>
> curl_easy_getinfo(curl, CURLINFO_SOCKET, &local);
>
> /* transfer data */
>
> curl_easy_cleanup(curl);
> }
>
> curl_global_cleanup();
>
>
>
>
> and then specify the proxy with an environment variable, I should get the
> socket for the transfer after the proxy connection and authentication have
> been completed.
>
> But if I don't set any environment variables for the proxy, do I get a
> direct connection to my target? Or, will I get some error condition?
>
> Is my question clear?
>
> I would like to dynamically control whether or not the proxy is used from
> the environment variables...and get a usable socket (either direct or
> proxytunneled) for my raw data transfer.
>
> Thanks,
>
> ...Karl
>
>
>

-- 
m. allan noah
IT Director, TfHS.net
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