NAME

CURLOPT_IPRESOLVE - IP protocol version to use

SYNOPSIS

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_IPRESOLVE, long resolve);

DESCRIPTION

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

EXAMPLE

int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
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);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}

AVAILABILITY

Added in curl 7.10.8

RETURN VALUE

Returns CURLE_OK

SEE ALSO

CURLOPT_HTTP_VERSION(3), CURLOPT_RESOLVE(3), CURLOPT_SSLVERSION(3)