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.

5 files changed, 23 insertions, 14 deletions

diff --git a/docs/cmdline-opts/preproxy.d b/docs/cmdline-opts/preproxy.d
index ebef4ab07..b8eb77fa4 100644
--- a/docs/cmdline-opts/preproxy.d
+++ b/docs/cmdline-opts/preproxy.d
@@ -3,8 +3,9 @@ Arg: [protocol://]host[:port]
 Help: Use this proxy first
 Added: 7.52.0
 ---
-Use the specified proxy before connecting to the ordinary proxy. Hence pre
-proxy. A pre proxy must be a SOCKS speaking proxy.
+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
diff --git a/docs/cmdline-opts/socks4.d b/docs/cmdline-opts/socks4.d
index 46354408e..11f6ae033 100644
--- a/docs/cmdline-opts/socks4.d
+++ b/docs/cmdline-opts/socks4.d
@@ -6,12 +6,14 @@ Added: 7.15.2
 Use the specified SOCKS4 proxy. If the port number is not specified, it is
 assumed at port 1080.
 
+This option overrides any previous use of --proxy, as they are mutually
+exclusive.
+
 Since 7.21.7, this option is superfluous since you can specify a socks4 proxy
 with --proxy using a socks4:// protocol prefix.
 
-This option typically overrides any previous use of --proxy; however since
-7.52.0 if --proxy is used to specify an HTTP or HTTPS proxy then curl will
-attempt to use it with the SOCKS proxy. In such a case curl first connects to
+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.
diff --git a/docs/cmdline-opts/socks4a.d b/docs/cmdline-opts/socks4a.d
index c7663eebd..ae254ae0e 100644
--- a/docs/cmdline-opts/socks4a.d
+++ b/docs/cmdline-opts/socks4a.d
@@ -6,12 +6,14 @@ Added: 7.18.0
 Use the specified SOCKS4a proxy. If the port number is not specified, it is
 assumed at port 1080.
 
+This option overrides any previous use of --proxy, as they are mutually
+exclusive.
+
 Since 7.21.7, this option is superfluous since you can specify a socks4a proxy
 with --proxy using a socks4a:// protocol prefix.
 
-This option typically overrides any previous use of --proxy; however since
-7.52.0 if --proxy is used to specify an HTTP or HTTPS proxy then curl will
-attempt to use it with the SOCKS proxy. In such a case curl first connects to
+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.
diff --git a/docs/cmdline-opts/socks5-hostname.d b/docs/cmdline-opts/socks5-hostname.d
index 87bc44a8e..9d9d946e5 100644
--- a/docs/cmdline-opts/socks5-hostname.d
+++ b/docs/cmdline-opts/socks5-hostname.d
@@ -6,12 +6,14 @@ Added: 7.18.0
 Use the specified SOCKS5 proxy (and let the proxy resolve the host name). If
 the port number is not specified, it is assumed at port 1080.
 
+This option overrides any previous use of --proxy, as they are mutually
+exclusive.
+
 Since 7.21.7, this option is superfluous since you can specify a socks5
 hostname proxy with --proxy using a socks5h:// protocol prefix.
 
-This option typically overrides any previous use of --proxy; however since
-7.52.0 if --proxy is used to specify an HTTP or HTTPS proxy then curl will
-attempt to use it with the SOCKS proxy. In such a case curl first connects to
+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.
diff --git a/docs/cmdline-opts/socks5.d b/docs/cmdline-opts/socks5.d
index aa07afeb1..22fae7629 100644
--- a/docs/cmdline-opts/socks5.d
+++ b/docs/cmdline-opts/socks5.d
@@ -6,12 +6,14 @@ Added: 7.18.0
 Use the specified SOCKS5 proxy - but resolve the host name locally. If the
 port number is not specified, it is assumed at port 1080.
 
+This option overrides any previous use of --proxy, as they are mutually
+exclusive.
+
 Since 7.21.7, this option is superfluous since you can specify a socks5 proxy
 with --proxy using a socks5:// protocol prefix.
 
-This option typically overrides any previous use of --proxy; however since
-7.52.0 if --proxy is used to specify an HTTP or HTTPS proxy then curl will
-attempt to use it with the SOCKS proxy. In such a case curl first connects to
+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.