plucky (3) CURLOPT_PROXY.3.gz

NAME

       CURLOPT_PROXY - proxy to use

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY, char *proxy);

DESCRIPTION

       Set  the  proxy  to  use  for  transfers  with  this  easy  handle. The parameter should be a char * to a
       null-terminated string holding the hostname 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 (but discouraged) be specified with the separate  option  CURLOPT_PROXYPORT(3).  If
       not specified, libcurl defaults to using port 1080 for proxies.

       The proxy string may be prefixed with [scheme]:// to specify which kind of proxy is used.

       Using  this option multiple times makes the last set string override the previous ones. Set it to NULL to
       disable its use again.

       The application does not have to keep the string around after setting this option.

       http://
              HTTP Proxy. Default when no scheme or proxy type is specified.

       https://
              HTTPS Proxy. (Added in 7.52.0 for OpenSSL and GnuTLS Since 7.87.0,  it  also  works  for  BearSSL,
              mbedTLS, Rustls, Schannel, Secure Transport and wolfSSL.)

              This  uses  HTTP/1  by default. Setting CURLOPT_PROXYTYPE(3) to CURLPROXY_HTTPS2 allows libcurl to
              negotiate using HTTP/2 with proxy.

       socks4://
              SOCKS4 Proxy.

       socks4a://
              SOCKS4a Proxy. Proxy resolves URL hostname.

       socks5://
              SOCKS5 Proxy.

       socks5h://
              SOCKS5 Proxy. Proxy resolves URL hostname.

       Without a scheme prefix, CURLOPT_PROXYTYPE(3) can be used to specify  which  kind  of  proxy  the  string
       identifies.

       When you tell the library to use an HTTP proxy, libcurl transparently converts operations to HTTP even if
       you specify an FTP URL etc. This may have an impact on what other features of the library  you  can  use,
       such  as  CURLOPT_QUOTE(3)  and similar FTP specifics that do not work unless you tunnel through the HTTP
       proxy. Such tunneling is activated with CURLOPT_HTTPPROXYTUNNEL(3).

       Setting the proxy string to "" (an empty string) explicitly disables the use of a proxy, even if there is
       an environment variable set for it.

       Unix  domain  sockets are supported for socks proxies since 7.84.0. Set localhost for the host part. e.g.
       socks5h://localhost/path/to/socket.sock

       When you set a hostname to use, do not assume that there is any particular single port number used widely
       for proxies. Specify it.

       When a proxy is used, the active FTP mode as set with CUROPT_FTPPORT(3), cannot be used.

       Doing FTP over an HTTP proxy without CURLOPT_HTTPPROXYTUNNEL(3) set makes libcurl do HTTP with an FTP URL
       over  the  proxy.  For  such  transfers,  common  FTP  specific  options  do  not   work,   for   example
       CURLOPT_USE_SSL(3).

Authentication

       The  proxy  can  also  be  specified with its associated credentials like for ordinary URLs in the style:
       scheme://username:password@hostname

       Alternatively, set them using CURLOPT_PROXYUSERNAME(3) and CURLOPT_PROXYPASSWORD(3).

Environment variables

       libcurl respects the proxy environment variables named http_proxy, ftp_proxy,  sftp_proxy  etc.  If  set,
       libcurl  uses  the specified proxy for that URL scheme. For an "FTP://" URL, the ftp_proxy is considered.
       all_proxy is used if no protocol specific proxy was set.

       If no_proxy (or NO_PROXY) is set, it is the exact equivalent of setting the CURLOPT_NOPROXY(3) option.

       The CURLOPT_PROXY(3) and CURLOPT_NOPROXY(3) options override environment variables.

DEFAULT

       NULL

PROTOCOLS

       This functionality affects all supported protocols

EXAMPLE

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/file.txt");
           curl_easy_setopt(curl, CURLOPT_PROXY, "http://proxy:80");
           curl_easy_perform(curl);
         }
       }

HISTORY

       Since 7.14.1 the proxy environment variable names can include the protocol scheme.

       Since 7.21.7 the proxy string supports the socks protocols as "schemes".

       Since 7.50.2, unsupported schemes in proxy strings cause libcurl to return error.

AVAILABILITY

       Added in curl 7.1

RETURN VALUE

       curl_easy_setopt(3) returns a CURLcode indicating success or error.

       CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).

SEE ALSO

       CURLOPT_HTTPPROXYTUNNEL(3), CURLOPT_PRE_PROXY(3), CURLOPT_PROXYPORT(3), CURLOPT_PROXYTYPE(3)