curl/docs/libcurl/opts/CURLOPT_SSL_EC_CURVES.md
Daniel Stenberg e694c8284a
docs/libcurl/opts: clarify the return values
Expand a little.

- mention the type name of the return code
- avoid stating which exact return codes that might be returned, as that
  varies over time, builds and conditions
- avoid stating some always return OK
- refer to the manpage documenting all the return codes

Closes #15900
2025-01-02 17:13:33 +01:00

72 lines
1.5 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_SSL_EC_CURVES
Section: 3
Source: libcurl
See-also:
- CURLOPT_SSL_CIPHER_LIST (3)
- CURLOPT_SSL_OPTIONS (3)
- CURLOPT_TLS13_CIPHERS (3)
Protocol:
- TLS
TLS-backend:
- OpenSSL
- wolfSSL
Added-in: 7.73.0
---
# NAME
CURLOPT_SSL_EC_CURVES - key exchange curves
# SYNOPSIS
~~~c
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_EC_CURVES, char *list);
~~~
# DESCRIPTION
Pass a string as parameter with a colon delimited list of Elliptic curve (EC)
algorithms. This option defines the client's key exchange algorithms in the
SSL handshake (if the SSL backend libcurl is built to use supports it).
The application does not have to keep the string around after setting this
option.
Using this option multiple times makes the last set string override the
previous ones. Set it to NULL to restore back to internal default.
# DEFAULT
"", embedded in SSL backend
# %PROTOCOLS%
# EXAMPLE
~~~c
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_SSL_EC_CURVES, "X25519:P-521");
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
~~~
# %AVAILABILITY%
# 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).