1---
2c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
3SPDX-License-Identifier: curl
4Title: CURLOPT_SSL_SESSIONID_CACHE
5Section: 3
6Source: libcurl
7See-also:
8  - CURLOPT_DNS_CACHE_TIMEOUT (3)
9  - CURLOPT_MAXAGE_CONN (3)
10  - CURLOPT_MAXLIFETIME_CONN (3)
11  - CURLOPT_SSLVERSION (3)
12---
13
14# NAME
15
16CURLOPT_SSL_SESSIONID_CACHE - use the SSL session-ID cache
17
18# SYNOPSIS
19
20~~~c
21#include <curl/curl.h>
22
23CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_SESSIONID_CACHE,
24                         long enabled);
25~~~
26
27# DESCRIPTION
28
29Pass a long set to 0 to disable libcurl's use of SSL session-ID caching. Set
30this to 1 to enable it. By default all transfers are done using the cache
31enabled. While nothing ever should get hurt by attempting to reuse SSL
32session-IDs, there seem to be or have been broken SSL implementations in the
33wild that may require you to disable this in order for you to succeed.
34
35# DEFAULT
36
371
38
39# PROTOCOLS
40
41All TLS-based
42
43# EXAMPLE
44
45~~~c
46int main(void)
47{
48  CURL *curl = curl_easy_init();
49  if(curl) {
50    CURLcode res;
51    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
52    /* switch off session-id use! */
53    curl_easy_setopt(curl, CURLOPT_SSL_SESSIONID_CACHE, 0L);
54    res = curl_easy_perform(curl);
55    curl_easy_cleanup(curl);
56  }
57}
58~~~
59
60# AVAILABILITY
61
62Added in 7.16.0
63
64# RETURN VALUE
65
66Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
67