curl/docs/libcurl/opts/CURLINFO_TLS_SESSION.md
Daniel Stenberg eefcc1bda4
docs: introduce "curldown" for libcurl man page format
curldown is this new file format for libcurl man pages. It is markdown
inspired with differences:

- Each file has a set of leading headers with meta-data
- Supports a small subset of markdown
- Uses .md file extensions for editors/IDE/GitHub to treat them nicely
- Generates man pages very similar to the previous ones
- Generates man pages that still convert nicely to HTML on the website
- Detects and highlights mentions of curl symbols automatically (when
  their man page section is specified)

tools:

- cd2nroff: converts from curldown to nroff man page
- nroff2cd: convert an (old) nroff man page to curldown
- cdall: convert many nroff pages to curldown versions
- cd2cd: verifies and updates a curldown to latest curldown

This setup generates .3 versions of all the curldown versions at build time.

CI:

Since the documentation is now technically markdown in the eyes of many
things, the CI runs many more tests and checks on this documentation,
including proselint, link checkers and tests that make sure we capitalize the
first letter after a period...

Closes #12730
2024-01-23 00:29:02 +01:00

76 lines
1.9 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
SPDX-License-Identifier: curl
Title: CURLINFO_TLS_SESSION
Section: 3
Source: libcurl
See-also:
- CURLINFO_TLS_SSL_PTR (3)
- curl_easy_getinfo (3)
- curl_easy_setopt (3)
---
# NAME
CURLINFO_TLS_SESSION - get TLS session info
# SYNOPSIS
~~~c
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_TLS_SESSION,
struct curl_tlssessioninfo **session);
~~~
# DESCRIPTION
**This option has been superseded** by CURLINFO_TLS_SSL_PTR(3) which
was added in 7.48.0. The only reason you would use this option instead is if
you could be using a version of libcurl earlier than 7.48.0.
This option is exactly the same as CURLINFO_TLS_SSL_PTR(3) except in the
case of OpenSSL. If the session *backend* is CURLSSLBACKEND_OPENSSL the
session *internals* pointer varies depending on the option:
CURLINFO_TLS_SESSION(3) OpenSSL session *internals* is **SSL_CTX ***.
CURLINFO_TLS_SSL_PTR(3) OpenSSL session *internals* is **SSL ***.
You can obtain an **SSL_CTX** pointer from an SSL pointer using OpenSSL
function *SSL_get_SSL_CTX(3)*. Therefore unless you need compatibility
with older versions of libcurl use CURLINFO_TLS_SSL_PTR(3). Refer to
that document for more information.
# PROTOCOLS
All TLS-based
# EXAMPLE
~~~c
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
struct curl_tlssessioninfo *tls;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
res = curl_easy_perform(curl);
if(res)
printf("error: %s\n", curl_easy_strerror(res));
curl_easy_getinfo(curl, CURLINFO_TLS_SESSION, &tls);
curl_easy_cleanup(curl);
}
}
~~~
# AVAILABILITY
Added in 7.34.0. Deprecated since 7.48.0 and supported OpenSSL, GnuTLS, and
NSS only up until this version was released.
# RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.