CURLOPT_IPRESOLVE3
Ip protocol version to use
Usage
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_IPRESOLVE, long resolve);
Overview
Allows an application to select what kind of IP addresses to use when establishing a connection or choosing one from the connection pool. This is interesting when using hostnames that resolve to more than one IP family.
If the URL provided for a transfer contains a numerical IP version as a host name, this option does not override or prohibit libcurl from using that IP version.
Available values for this option are:
CURL_IPRESOLVE_WHATEVER
|
Default, can use addresses of all IP versions that your system allows. |
|---|---|
CURL_IPRESOLVE_V4
|
Uses only IPv4 addresses. |
CURL_IPRESOLVE_V6
|
Uses only IPv6 addresses. |
Default
CURL_IPRESOLVE_WHATEVER
Protocols
This functionality affects all supported protocols
Examples
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode result;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
/* of all addresses example.com resolves to, only IPv6 ones are used */
curl_easy_setopt(curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V6);
result = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
Return value
curl_easy_setopt(3) returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).
Releases
7 releases since Debian 8 (Jessie); the text changed 6 times.