Merge bitcoin#9910: Docs: correct and elaborate -rpcbind doc

e5b449c Docs: correct and elaborate -rpcbind doc (Ian Kelling)

Tree-SHA512: e1cdaa32f7248f304d463e3f37d7d5da23ee0e506bd453420b87f4cc9c704cc30214e41c9266294890d65f2ee270f9355f38b542e8c01452637bdbba8273c755

src/init.cpp

@@ -623,7 +623,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageGroup(_("RPC server options:"));
     strUsage += HelpMessageOpt("-server", _("Accept command line and JSON-RPC commands"));
     strUsage += HelpMessageOpt("-rest", strprintf(_("Accept public REST requests (default: %u)"), DEFAULT_REST_ENABLE));
-    strUsage += HelpMessageOpt("-rpcbind=<addr>", _("Bind to given address to listen for JSON-RPC connections. Use [host]:port notation for IPv6. This option can be specified multiple times (default: bind to all interfaces)"));
+    strUsage += HelpMessageOpt("-rpcbind=<addr>[:port]", _("Bind to given address to listen for JSON-RPC connections. This option is ignored unless -rpcallowip is also passed. Port is optional and overrides -rpcport. Use [host]:port notation for IPv6. This option can be specified multiple times (default: 127.0.0.1 and ::1 i.e., localhost, or if -rpcallowip has been specified, 0.0.0.0 and :: i.e., all addresses)"));
     strUsage += HelpMessageOpt("-rpccookiefile=<loc>", _("Location of the auth cookie (default: data dir)"));
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));