1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
|
.\" **************************************************************************
.\" * _ _ ____ _
.\" * Project ___| | | | _ \| |
.\" * / __| | | | |_) | |
.\" * | (__| |_| | _ <| |___
.\" * \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
.\" * are also available at https://curl.haxx.se/docs/copyright.html.
.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" **************************************************************************
.\"
.TH CURLOPT_PRE_PROXY 3 "16 Nov 2016" "libcurl 7.52.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_PRE_PROXY \- set pre-proxy to use
.SH SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PRE_PROXY, char *preproxy);
.SH DESCRIPTION
Set the \fIpreproxy\fP to use for the upcoming request. The parameter
should be a char * to a zero terminated string holding the host name or dotted
numerical IP address. A numerical IPv6 address must be written within
[brackets].
To specify port number in this string, append :[port] to the end of the host
name. The proxy's port number may optionally be specified with the separate
option \fICURLOPT_PROXYPORT(3)\fP. If not specified, libcurl will default to
using port 1080 for proxies.
A pre proxy is a SOCKS proxy that curl connects to before it connects to the
HTTP(S) proxy specified in the \fICURLOPT_PROXY\fP option. The pre proxy can
only be a SOCKS proxy.
The pre proxy string should be prefixed with [scheme]:// to specify which kind
of socks is used. Use socks4://, socks4a://, socks5:// or socks5h:// (the last
one to enable socks5 and asking the proxy to do the resolving, also known as
\fICURLPROXY_SOCKS5_HOSTNAME\fP type) to request the specific SOCKS version to
be used. Otherwise SOCKS4 is used as default.
Setting the pre proxy string to "" (an empty string) will explicitly disable
the use of a pre proxy.
The application does not have to keep the string around after setting this
option.
.SH DEFAULT
Default is NULL, meaning no pre proxy is used.
When you set a host name to use, do not assume that there's any particular
single port number used widely for proxies. Specify it!
.SH PROTOCOLS
All except file://. Note that some protocols don't do very well over proxy.
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/file.txt");
curl_easy_setopt(curl, CURLOPT_PREPROXY, "socks4://socks-proxy:1080");
curl_easy_setopt(curl, CURLOPT_PROXY, "http://proxy:80");
curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Added in 7.52.0
.SH RETURN VALUE
Returns CURLE_OK if proxies are supported, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
.SH "SEE ALSO"
.BR CURLOPT_PROXY "(3), " CURLOPT_HTTPPROXYTUNNEL "(3), "
|
