eefcc1bda4
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
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| c | SPDX-License-Identifier | Title | Section | Source | See-also | ||||
|---|---|---|---|---|---|---|---|---|---|
| Copyright (C) Daniel Stenberg, <daniel.se>, et al. | curl | CURLOPT_HTTP_VERSION | 3 | libcurl |
|
NAME
CURLOPT_HTTP_VERSION - HTTP protocol version to use
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP_VERSION, long version);
DESCRIPTION
Pass version a long, set to one of the values described below. They ask libcurl to use the specific HTTP versions.
Note that the HTTP version is just a request. libcurl still prioritizes to reuse existing connections so it might then reuse a connection using a HTTP version you have not asked for.
CURL_HTTP_VERSION_NONE
We do not care about what version the library uses. libcurl uses whatever it thinks fit.
CURL_HTTP_VERSION_1_0
Enforce HTTP 1.0 requests.
CURL_HTTP_VERSION_1_1
Enforce HTTP 1.1 requests.
CURL_HTTP_VERSION_2_0
Attempt HTTP 2 requests. libcurl falls back to HTTP 1.1 if HTTP 2 cannot be negotiated with the server. (Added in 7.33.0)
When libcurl uses HTTP/2 over HTTPS, it does not itself insist on TLS 1.2 or higher even though that is required by the specification. A user can add this version requirement with CURLOPT_SSLVERSION(3).
The alias CURL_HTTP_VERSION_2 was added in 7.43.0 to better reflect the actual protocol name.
CURL_HTTP_VERSION_2TLS
Attempt HTTP 2 over TLS (HTTPS) only. libcurl falls back to HTTP 1.1 if HTTP 2 cannot be negotiated with the HTTPS server. For clear text HTTP servers, libcurl uses 1.1. (Added in 7.47.0)
CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE
Issue non-TLS HTTP requests using HTTP/2 without HTTP/1.1 Upgrade. It requires prior knowledge that the server supports HTTP/2 straight away. HTTPS requests still do HTTP/2 the standard way with negotiated protocol version in the TLS handshake. (Added in 7.49.0)
CURL_HTTP_VERSION_3
(Added in 7.66.0) This option makes libcurl attempt to use HTTP/3 to the host given in the URL, with fallback to earlier HTTP versions if needed.
CURL_HTTP_VERSION_3ONLY
(Added in 7.88.0) Setting this makes libcurl attempt to use HTTP/3 directly to server given in the URL and does not downgrade to earlier HTTP version if the server does not support HTTP/3.
DEFAULT
Since curl 7.62.0: CURL_HTTP_VERSION_2TLS
Before that: CURL_HTTP_VERSION_1_1
PROTOCOLS
HTTP
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode ret;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_HTTP_VERSION,
(long)CURL_HTTP_VERSION_2TLS);
ret = curl_easy_perform(curl);
if(ret == CURLE_HTTP_RETURNED_ERROR) {
/* an HTTP response error problem */
}
}
}
AVAILABILITY
Along with HTTP
RETURN VALUE
Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.