************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel (at] haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.haxx.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ************************************************************************** CURLOPT_DNS_CACHE_TIMEOUT 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
NAME
CURLOPT_DNS_CACHE_TIMEOUT - set life-time for DNS cache entries
SYNOPSIS
#include <
curl/
curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_CACHE_TIMEOUT, long age);
DESCRIPTION
Pass a long, this sets the timeout in seconds. Name resolves will be kept in
memory and used for this number of seconds. Set to zero to completely disable
caching, or set to -1 to make the cached entries remain forever. By default,
libcurl caches this info for 60 seconds.
The name resolve functions of various libc implementations don't re-read name
server information unless explicitly told so (for example, by calling
res_init(3)). This may cause libcurl to keep using the older server even
if DHCP has updated the server info, and this may look like a DNS cache issue
to the casual libcurl-app user.
Note that DNS entries have a "TTL" property but libcurl doesn't use that. This
DNS cache timeout is entirely speculative that a name will resolve to the same
address for a certain small amount of time into the future.
DEFAULT
60
PROTOCOLS
All
EXAMPLE
TODO
AVAILABILITY
Always
RETURN VALUE
Returns CURLE_OK
"SEE ALSO"
CURLOPT_DNS_USE_GLOBAL_CACHE "(3), " CURLOPT_DNS_SERVERS "(3), "