Manpage logo

CURLOPT_SSL_SESSIONID_CACHE - use the SSL session-ID cache

NAME  SYNOPSIS  DESCRIPTION  DEFAULT  PROTOCOLS  EXAMPLE  AVAILABILITY  RETURN VALUE  SEE ALSO 

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

This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

All TLS backends support this option.

EXAMPLE

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

AVAILABILITY

Added in curl 7.16.0

RETURN VALUE

curl_easy_setopt(3) returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non−zero means an error occurred, see libcurl−errors(3).

SEE ALSO

CURLOPT_DNS_CACHE_TIMEOUT(3), CURLOPT_MAXAGE_CONN(3), CURLOPT_MAXLIFETIME_CONN(3), CURLOPT_SSLVERSION(3)


Updated 2026-06-01 - jenkler.se | uex.se