CURLOPT_CA_CACHE_TIMEOUT(3)

NAME
CURLOPT_CA_CACHE_TIMEOUT - life-time for cached certificate stores

SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CA_CACHE_TIMEOUT, long age);

DESCRIPTION
Pass a long, this sets the timeout in seconds. This tells libcurl the maximum time any cached certificate store it has in memory may be kept and reused for new connections. Once the timeout has expired, a subsequent fetch requiring a certificate store will have to build a new one.

Building a certificate store from a CURLOPT_CAINFO file is a slow operation so curl may cache the generated certificate store internally to speed up future connections.

Set to zero to completely disable caching, or set to -1 to retain the cached store remain forever. By default, libcurl caches this info for 24 hours.

DEFAULT
86400 (24 hours)

PROTOCOLS
All

EXAMPLE
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");

  /* only reuse certificate stores for a short time */
  curl_easy_setopt(curl, CURLOPT_CA_CACHE_TIMEOUT, 60L);

  ret = curl_easy_perform(curl);

  /* in this second request, the cache will not be used if more than
     sixty seconds have passed since the previous connection */
  ret = curl_easy_perform(curl);

  curl_easy_cleanup(curl);
}

AVAILABILITY
This option was added in curl 7.87.0.

Currently the only SSL backend to implement this certificate store caching functionality is the OpenSSL (and forks) backend.

RETURN VALUE
Returns CURLE_OK

SEE ALSO
CURLOPT_CAINFO(3), CURLOPT_CAINFO_BLOB(3), CURLOPT_CAPATH(3), CURLOPT_SSL_VERIFYPEER(3), CURLOPT_SSL_VERIFYHOST(3),