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

1.9 KiB

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

NAME

CURLINFO_TLS_SESSION - get TLS session info

SYNOPSIS

#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This option has been superseded by CURLINFO_TLS_SSL_PTR(3) which was added in 7.48.0.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

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.