+++ /dev/null
-<!--
-Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
-
-SPDX-License-Identifier: curl
--->
-
-# Alt-Svc
-
-curl features support for the Alt-Svc: HTTP header.
-
-## Enable Alt-Svc in build
-
-`./configure --enable-alt-svc`
-
-(enabled by default since 7.73.0)
-
-## Standard
-
-[RFC 7838](https://datatracker.ietf.org/doc/html/rfc7838)
-
-# Alt-Svc cache file format
-
-This is a text based file with one line per entry and each line consists of nine
-space separated fields.
-
-## Example
-
- h2 quic.tech 8443 h3-22 quic.tech 8443 "20190808 06:18:37" 0 0
-
-## Fields
-
-1. The ALPN id for the source origin
-2. The hostname for the source origin
-3. The port number for the source origin
-4. The ALPN id for the destination host
-5. The hostname for the destination host
-6. The port number for the destination host
-7. The expiration date and time of this entry within double quotes. The date format is "YYYYMMDD HH:MM:SS" and the time zone is GMT.
-8. Boolean (1 or 0) if "persist" was set for this entry
-9. Integer priority value (not currently used)
-
-If the hostname is an IPv6 numerical address, it is stored with brackets such
-as `[::1]`.
-
-# TODO
-
-- handle multiple response headers, when one of them says `clear` (should
- override them all)
-- using `Age:` value for caching age as per spec
-- `CURLALTSVC_IMMEDIATELY` support
+++ /dev/null
-<!--
-Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
-
-SPDX-License-Identifier: curl
--->
-
-# HSTS support
-
-HTTP Strict-Transport-Security. Added as experimental in curl
-7.74.0. Supported "for real" since 7.77.0.
-
-## Standard
-
-[HTTP Strict Transport Security](https://datatracker.ietf.org/doc/html/rfc6797)
-
-## Behavior
-
-libcurl features an in-memory cache for HSTS hosts, so that subsequent
-HTTP-only requests to a hostname present in the cache gets internally
-"redirected" to the HTTPS version.
-
-## `curl_easy_setopt()` options:
-
- - `CURLOPT_HSTS_CTRL` - enable HSTS for this easy handle
- - `CURLOPT_HSTS` - specify filename where to store the HSTS cache on close
- (and possibly read from at startup)
-
-## curl command line options
-
- - `--hsts [filename]` - enable HSTS, use the file as HSTS cache. If filename
- is `""` (no length) then no file is used, only in-memory cache.
-
-## HSTS cache file format
-
-Lines starting with `#` are ignored.
-
-For each hsts entry:
-
- [host name] "YYYYMMDD HH:MM:SS"
-
-The `[host name]` is dot-prefixed if it includes subdomains.
-
-The time stamp is when the entry expires.
-
-## Possible future additions
-
- - `CURLOPT_HSTS_PRELOAD` - provide a set of HSTS hostnames to load first
- - ability to save to something else than a file
+++ /dev/null
-<!--
-Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
-
-SPDX-License-Identifier: curl
--->
-
-HTTP/2 with curl
-================
-
-[HTTP/2 Spec](https://www.rfc-editor.org/rfc/rfc7540.txt)
-[http2 explained](https://daniel.haxx.se/http2/)
-
-Build prerequisites
--------------------
- - nghttp2
- - OpenSSL, LibreSSL, BoringSSL, GnuTLS, mbedTLS, wolfSSL or Schannel
- with a new enough version.
-
-[nghttp2](https://nghttp2.org/)
--------------------------------
-
-libcurl uses this 3rd party library for the low level protocol handling
-parts. The reason for this is that HTTP/2 is much more complex at that layer
-than HTTP/1.1 (which we implement on our own) and that nghttp2 is an already
-existing and well functional library.
-
-We require at least version 1.12.0.
-
-Over an http:// URL
--------------------
-
-If `CURLOPT_HTTP_VERSION` is set to `CURL_HTTP_VERSION_2_0`, libcurl includes
-an upgrade header in the initial request to the host to allow upgrading to
-HTTP/2.
-
-Possibly we can later introduce an option that causes libcurl to fail if it is
-not possible to upgrade. Possibly we introduce an option that makes libcurl
-use HTTP/2 at once over http://
-
-Over an https:// URL
---------------------
-
-If `CURLOPT_HTTP_VERSION` is set to `CURL_HTTP_VERSION_2_0`, libcurl uses ALPN
-to negotiate which protocol to continue with. Possibly introduce an option
-that causes libcurl to fail if not possible to use HTTP/2.
-
-`CURL_HTTP_VERSION_2TLS` was added in 7.47.0 as a way to ask libcurl to prefer
-HTTP/2 for HTTPS but stick to 1.1 by default for plain old HTTP connections.
-
-ALPN is the TLS extension that HTTP/2 is expected to use.
-
-`CURLOPT_SSL_ENABLE_ALPN` is offered to allow applications to explicitly
-disable ALPN.
-
-Multiplexing
-------------
-
-Starting in 7.43.0, libcurl fully supports HTTP/2 multiplexing, which is the
-term for doing multiple independent transfers over the same physical TCP
-connection.
-
-To take advantage of multiplexing, you need to use the multi interface and set
-`CURLMOPT_PIPELINING` to `CURLPIPE_MULTIPLEX`. With that bit set, libcurl
-attempts to reuse existing HTTP/2 connections and just add a new stream over
-that when doing subsequent parallel requests.
-
-While libcurl sets up a connection to an HTTP server there is a period during
-which it does not know if it can pipeline or do multiplexing and if you add
-new transfers in that period, libcurl defaults to starting new connections for
-those transfers. With the new option `CURLOPT_PIPEWAIT` (added in 7.43.0), you
-can ask that a transfer should rather wait and see in case there is a
-connection for the same host in progress that might end up being possible to
-multiplex on. It favors keeping the number of connections low to the cost of
-slightly longer time to first byte transferred.
-
-Applications
-------------
-
-We hide HTTP/2's binary nature and convert received HTTP/2 traffic to headers
-in HTTP 1.1 style. This allows applications to work unmodified.
-
-curl tool
----------
-
-curl offers the `--http2` command line option to enable use of HTTP/2.
-
-curl offers the `--http2-prior-knowledge` command line option to enable use of
-HTTP/2 without HTTP/1.1 Upgrade.
-
-Since 7.47.0, the curl tool enables HTTP/2 by default for HTTPS connections.
-
-curl tool limitations
----------------------
-
-The command line tool does not support HTTP/2 server push. It supports
-multiplexing when the parallel transfer option is used.
-
-HTTP Alternative Services
--------------------------
-
-Alt-Svc is an extension with a corresponding frame (ALTSVC) in HTTP/2 that
-tells the client about an alternative "route" to the same content for the same
-origin server that you get the response from. A browser or long-living client
-can use that hint to create a new connection asynchronously. For libcurl, we
-may introduce a way to bring such clues to the application and/or let a
-subsequent request use the alternate route automatically.
-
-[Detailed in RFC 7838](https://datatracker.ietf.org/doc/html/rfc7838)
EXTRA_DIST = \
$(CURLPAGES) \
$(INTERNALDOCS) \
- ALTSVC.md \
BINDINGS.md \
BUG-BOUNTY.md \
BUGS.md \
GOVERNANCE.md \
HELP-US.md \
HISTORY.md \
- HSTS.md \
HTTP-COOKIES.md \
- HTTP2.md \
HTTP3.md \
INSTALL \
INSTALL-CMAKE.md \
MAIL-ETIQUETTE.md \
MANUAL.md \
options-in-versions \
- PARALLEL-TRANSFERS.md \
README.md \
RELEASE-PROCEDURE.md \
RUSTLS.md \
+++ /dev/null
-<!--
-Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
-
-SPDX-License-Identifier: curl
--->
-
-# Parallel transfers
-
-curl 7.66.0 introduced support for doing multiple transfers simultaneously; in
-parallel.
-
-## -Z, --parallel
-
-When this command line option is used, curl performs the transfers given to it
-at the same time. It does up to `--parallel-max` concurrent transfers, with a
-default value of 50.
-
-## Progress meter
-
-The progress meter that is displayed when doing parallel transfers is
-completely different than the regular one used for each single transfer.
-
- It shows:
-
- o percent download (if known, which means *all* transfers need to have a
- known size)
- o percent upload (if known, with the same caveat as for download)
- o total amount of downloaded data
- o total amount of uploaded data
- o number of transfers to perform
- o number of concurrent transfers being transferred right now
- o number of transfers queued up waiting to start
- o total time all transfers are expected to take (if sizes are known)
- o current time the transfers have spent so far
- o estimated time left (if sizes are known)
- o current transfer speed (the faster of upload/download speeds measured over
- the last few seconds)
-
-Example:
-
- DL% UL% Dled Uled Xfers Live Qd Total Current Left Speed
- 72 -- 37.9G 0 101 30 23 0:00:55 0:00:34 0:00:22 2752M
-
-## Behavior differences
-
-Connections are shared fine between different easy handles, but the
-"authentication contexts" are not. For example doing HTTP Digest auth with one
-handle for a particular transfer and then continue on with another handle that
-reuses the same connection, the second handle cannot send the necessary
-Authorization header at once since the context is only kept in the original
-easy handle.
-
-To fix this, the authorization state could be made possible to share with the
-share API as well, as a context per origin + path (realm?) basically.
-
-Visible in test 153, 1412 and more.
projects / thirdparty / curl.git / commitdiff
