curl/docs/libcurl/opts/CURLOPT_DNS_USE_GLOBAL_CACHE.md

---

c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Title: CURLOPT_DNS_USE_GLOBAL_CACHE Section: 3 Source: libcurl See-also:

• CURLOPT_DNS_CACHE_TIMEOUT (3)
• CURLOPT_SHARE (3) Protocol:
• All Added-in: 7.9.3 ---

NAME

CURLOPT_DNS_USE_GLOBAL_CACHE - global DNS cache

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_USE_GLOBAL_CACHE,
                          long enable);

DESCRIPTION

Has no function since 7.62.0. Do not use!

Pass a long. If the enable value is 1, it tells curl to use a global DNS cache that survives between easy handle creations and deletions. This is not thread-safe and this uses a global variable.

See CURLOPT_SHARE(3) and curl_share_init(3) for the correct way to share DNS cache between transfers.

DEFAULT

0

%PROTOCOLS%

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode ret;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    /* switch off the use of a global, thread unsafe, cache */
    curl_easy_setopt(curl, CURLOPT_DNS_USE_GLOBAL_CACHE, 0L);
    ret = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

DEPRECATED

Deprecated since 7.11.1. Functionality removed in 7.62.0.

%AVAILABILITY%

RETURN VALUE

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.