table of contents
other versions
- buster 7.64.0-4+deb10u2
- buster-backports 7.74.0-1.2~bpo10+1
- testing 7.74.0-1.2
- unstable 7.74.0-1.3
CURLOPT_HTTP_VERSION(3) | curl_easy_setopt options | CURLOPT_HTTP_VERSION(3) |
NAME¶
CURLOPT_HTTP_VERSION - specify HTTP protocol version to useSYNOPSIS¶
#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. This is not sensible to do unless you have a good reason. You have to set this option if you want to use libcurl's HTTP/2 support.Note that the HTTP version is just a request. libcurl will still prioritize to re-use an existing connection so it might then re-use a connection using a HTTP version you haven't asked for.
- CURL_HTTP_VERSION_NONE
- We don't care about what version the library uses. libcurl will use 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 will fall back to HTTP 1.1 if HTTP 2
can't be negotiated with the server. (Added in 7.33.0)
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 will fall back to HTTP 1.1 if HTTP 2 can't be negotiated with the HTTPS server. For clear text HTTP servers, libcurl will use 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 will still do HTTP/2 the standard way with negotiated protocol version in the TLS handshake. (Added in 7.49.0)
DEFAULT¶
Since curl 7.62.0: CURL_HTTP_VERSION_2TLSBefore that: CURL_HTTP_VERSION_1_1
PROTOCOLS¶
HTTPEXAMPLE¶
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, CURL_HTTP_VERSION_2TLS); ret = curl_easy_perform(curl); if(ret == CURLE_HTTP_RETURNED_ERROR) { /* an HTTP response error problem */ } }
AVAILABILITY¶
Along with HTTPRETURN VALUE¶
Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.SEE ALSO¶
CURLOPT_SSLVERSION(3), CURLOPT_HTTP200ALIASES(3), CURLOPT_HTTP09_ALLOWED(3),December 17, 2018 | libcurl 7.64.0 |