--socks4a

Use the specified SOCKS4a proxy. If the port number is not specified, it is assumed at port 1080. This asks the proxy to resolve the hostname.

To specify proxy on a Unix domain socket, use localhost for host, e.g. socks4a://localhost/path/to/socket.sock

This option overrides any previous use of --proxy, as they are mutually exclusive.

This option is superfluous since you can specify a socks4a proxy with --proxy using a socks4a:// protocol prefix. (Added in 7.21.7)

--preproxy can be used to specify a SOCKS proxy at the same time --proxy is used with an HTTP/HTTPS proxy (added in 7.52.0). In such a case, curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy.