curl/docs/cmdline-opts/preproxy.md

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Long: preproxy
Arg: [protocol://]host[:port]
Help: Use this proxy first
Added: 7.52.0
Category: proxy
Multi: single
See-also:
  - proxy
  - socks5
Example:
  - --preproxy socks5://proxy.example -x http://http.example $URL
---

# `--preproxy`

Use the specified SOCKS proxy before connecting to an HTTP or HTTPS --proxy. In
such a case curl first connects to the SOCKS proxy and then connects (through
SOCKS) to the HTTP or HTTPS proxy. Hence pre proxy.

The pre proxy string should be specified with a protocol:// prefix to specify
alternative proxy protocols. Use socks4://, socks4a://, socks5:// or
socks5h:// to request the specific SOCKS version to be used. No protocol
specified makes curl default to SOCKS4.

If the port number is not specified in the proxy string, it is assumed to be
1080.

User and password that might be provided in the proxy string are URL decoded
by curl. This allows you to pass in special characters such as @ by using %40
or pass in a colon with %3a.
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00			`---`
copyright: update all copyright lines and remove year ranges - they are mostly pointless in all major jurisdictions - many big corporations and projects already don't use them - saves us from pointless churn - git keeps history for us - the year range is kept in COPYING checksrc is updated to allow non-year using copyright statements Closes #10205 2023-01-02 20:51:48 +08:00			`c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.`
docs/cmdline-opts: add copyright and license identifier to each file gen.pl now insists on C: and SPDX-License-Identifier: fields to be present in all files. Closes #9002 2022-06-14 06:12:03 +08:00			`SPDX-License-Identifier: curl`
preproxy: renamed what was added as SOCKS_PROXY CURLOPT_SOCKS_PROXY -> CURLOPT_PRE_PROXY Added the corresponding --preroxy command line option. Sets a SOCKS proxy to connect to _before_ connecting to a HTTP(S) proxy. 2016-12-16 23:02:08 +08:00			`Long: preproxy`
			`Arg: [protocol://]host[:port]`
			`Help: Use this proxy first`
			`Added: 7.52.0`
docs: add categories to all cmdline opts Adapted gen.pl with 'listcats' This commit is a part of "--help me if you can" Closes #5680 2020-07-13 20:15:04 +08:00			`Category: proxy`
cmdline/docs: add a required 'multi' keyword for each option The keyword specifies how option works when specified multiple times: - single: the last provided value replaces the earlier ones - append: it supports being provided multiple times - boolean: on/off values - mutex: flag-like option that disable anoter flag The 'gen.pl' script then outputs the proper and unified language for each option's multi-use behavior in the generated man page. The multi: header is requires in each .d file and will cause build error if missing or set to an unknown value. Closes #9759 2022-10-18 16:39:43 +08:00			`Multi: single`
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00			`See-also:`
			`- proxy`
			`- socks5`
			`Example:`
			`- --preproxy socks5://proxy.example -x http://http.example $URL`
preproxy: renamed what was added as SOCKS_PROXY CURLOPT_SOCKS_PROXY -> CURLOPT_PRE_PROXY Added the corresponding --preroxy command line option. Sets a SOCKS proxy to connect to _before_ connecting to a HTTP(S) proxy. 2016-12-16 23:02:08 +08:00			`---`
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00
			# `--preproxy`

cmdline-opts/socks: Mention --preproxy in --socks opts - Document in --socks* opts they're still mutually exclusive of --proxy. Partial revert of 423a93c; I had misinterpreted the SOCKS proxy + HTTP/HTTPS proxy combination. - Document in --socks* opts that --preproxy can be used to specify a SOCKS proxy at the same time --proxy is used with an HTTP/HTTPS proxy. 2017-02-10 07:26:16 +08:00			`Use the specified SOCKS proxy before connecting to an HTTP or HTTPS --proxy. In`
			`such a case curl first connects to the SOCKS proxy and then connects (through`
			`SOCKS) to the HTTP or HTTPS proxy. Hence pre proxy.`
preproxy: renamed what was added as SOCKS_PROXY CURLOPT_SOCKS_PROXY -> CURLOPT_PRE_PROXY Added the corresponding --preroxy command line option. Sets a SOCKS proxy to connect to _before_ connecting to a HTTP(S) proxy. 2016-12-16 23:02:08 +08:00
			`The pre proxy string should be specified with a protocol:// prefix to specify`
			`alternative proxy protocols. Use socks4://, socks4a://, socks5:// or`
			`socks5h:// to request the specific SOCKS version to be used. No protocol`
cmdline-docs: use present tense, not future + some smaller cleanups Closes #11821 2023-09-08 20:32:29 +08:00			`specified makes curl default to SOCKS4.`
preproxy: renamed what was added as SOCKS_PROXY CURLOPT_SOCKS_PROXY -> CURLOPT_PRE_PROXY Added the corresponding --preroxy command line option. Sets a SOCKS proxy to connect to _before_ connecting to a HTTP(S) proxy. 2016-12-16 23:02:08 +08:00
			`If the port number is not specified in the proxy string, it is assumed to be`
			`1080.`

			`User and password that might be provided in the proxy string are URL decoded`
			`by curl. This allows you to pass in special characters such as @ by using %40`
			`or pass in a colon with %3a.`