Long: socks4
Arg: <host[:port]>
Help: SOCKS4 proxy on given host + port
Added: 7.15.2
Category: proxy
Example: --socks4 hostname:4096 $URL
---
Use the specified SOCKS4 proxy. If the port number is not specified, it is
assumed at port 1080. Using this socket type make curl resolve the host name
and passing the address on to the proxy.

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

This option is superfluous since you can specify a socks4 proxy with --proxy
using a socks4:// protocol prefix. (Added in 7.21.7)

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

If this option is used several times, the last one will be used.