---

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

• CURLOPT_DNS_CACHE_TIMEOUT (3)
• CURLOPT_MAXAGE_CONN (3)
• CURLOPT_MAXLIFETIME_CONN (3)
• CURLOPT_SSLVERSION (3)

---

NAME

CURLOPT_SSL_SESSIONID_CACHE - use the SSL session-ID cache

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_SESSIONID_CACHE,
                         long enabled);

DESCRIPTION

Pass a long set to 0 to disable libcurl's use of SSL session-ID caching. Set this to 1 to enable it. By default all transfers are done using the cache enabled. While nothing ever should get hurt by attempting to reuse SSL session-IDs, there seem to be or have been broken SSL implementations in the wild that may require you to disable this in order for you to succeed.

DEFAULT

1

PROTOCOLS

All TLS-based

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    /* switch off session-id use! */
    curl_easy_setopt(curl, CURLOPT_SSL_SESSIONID_CACHE, 0L);
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

AVAILABILITY

Added in 7.16.0

RETURN VALUE

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