.\" generated by cd2nroff 0.1 from CURLOPT_ADDRESS_SCOPE.md
.TH CURLOPT_ADDRESS_SCOPE 3 "2026-06-24" libcurl
.SH NAME
CURLOPT_ADDRESS_SCOPE \- scope id for IPv6 addresses
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ADDRESS_SCOPE, long scope);
.fi
.SH DESCRIPTION
Pass a long specifying the scope id value to use when connecting to IPv6 addresses.
.SH DEFAULT
0
.SH PROTOCOLS
This functionality affects all supported protocols
.SH EXAMPLE
.nf
#include <net/if.h> /* for if_nametoindex() */

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    long my_scope_id;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    my_scope_id = if_nametoindex("eth0");
    curl_easy_setopt(curl, CURLOPT_ADDRESS_SCOPE, my_scope_id);
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.19.0
.SH RETURN VALUE
\fIcurl_easy_setopt(3)\fP returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non\-zero means an error occurred, see
\fIlibcurl\-errors(3)\fP.
Returns CURLE_BAD_FUNCTION_ARGUMENT if set to a negative value.
.SH SEE ALSO
.BR CURLOPT_DEBUGFUNCTION (3),
.BR CURLOPT_STDERR (3)