cmd/rc: add --unix-socket option

This adds an additional StringVarP for unix-socket, and in case it's not
an empty string, uses fshttp.NewClientWithUnixSocket instead of
fshttp.NewClient.

cmd/rc/rc.go

@@ -23,21 +23,23 @@ import (
 )
 
 var (
-	noOutput  = false
-	url       = "http://localhost:5572/"
-	jsonInput = ""
-	authUser  = ""
-	authPass  = ""
-	loopback  = false
-	options   []string
-	arguments []string
+	noOutput   = false
+	url        = "http://localhost:5572/"
+	unixSocket = ""
+	jsonInput  = ""
+	authUser   = ""
+	authPass   = ""
+	loopback   = false
+	options    []string
+	arguments  []string
 )
 
 func init() {
 	cmd.Root.AddCommand(commandDefinition)
 	cmdFlags := commandDefinition.Flags()
 	flags.BoolVarP(cmdFlags, &noOutput, "no-output", "", noOutput, "If set, don't output the JSON result", "")
 	flags.StringVarP(cmdFlags, &url, "url", "", url, "URL to connect to rclone remote control", "")
+	flags.StringVarP(cmdFlags, &unixSocket, "unix-socket", "", unixSocket, "Path to a unix domain socket to dial to, instead of opening a TCP connection directly", "")
 	flags.StringVarP(cmdFlags, &jsonInput, "json", "", jsonInput, "Input JSON - use instead of key=value args", "")
 	flags.StringVarP(cmdFlags, &authUser, "user", "", "", "Username to use to rclone remote control", "")
 	flags.StringVarP(cmdFlags, &authPass, "pass", "", "", "Password to use to connect to rclone remote control", "")
@@ -201,7 +203,12 @@ func doCall(ctx context.Context, path string, in rc.Params) (out rc.Params, err
 	}
 
 	// Do HTTP request
-	client := fshttp.NewClient(ctx)
+	var client *http.Client
+	if unixSocket == "" {
+		client = fshttp.NewClient(ctx)
+	} else {
+		client = fshttp.NewClientWithUnixSocket(ctx, unixSocket)
+	}
 	url += path
 	data, err := json.Marshal(in)
 	if err != nil {