Add the serial read functionality and run into troubles with vim

agent.go

@@ -1,25 +1,46 @@
 package main
 
+// Create a new virtual serial device:
+// socat PTY,link=/dev/ttyS10 PTY,link=/dev/ttyS11
+
 import (
 	"log"
 	"os"
 	"path"
 
 	"github.com/fsnotify/fsnotify"
+	"github.com/tarm/serial"
 	"github.com/mkideal/cli"
 )
 
+// TODO: Make the error code optional (as a parameter)
 func stop() {
 	log.Println("Have a nice day.")
-	// TODO: Make the error code optional (as a parameter)
+	os.Exit(0)
-	os.Exit(1)
 }
 
-func waitAndExecuteCommandsFromDevice() {
+func waitAndExecuteCommandsFromDevice(device string) {
-	// TODO: Establish connection to the device
+	config := &serial.Config{Name: device, Baud: 115200}
-	// TODO: Wait for action loop
+	serial, err := serial.OpenPort(config)
-	// TODO: Execute action
+
-	// TODO: Wait for action loop ...
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	log.Printf("Open the connection to the n3rdpad over %s", device)
+
+	// Read from serial
+	buffer := make([]byte, 128)
+	for {
+		num, err := serial.Read(buffer)
+
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		// TODO: Do something with the incomind commands
+		log.Printf("%q", buffer[:num])
+	}
 }
 
 func watchForConfigChanges(configFile string) {
@@ -47,6 +68,10 @@ func watchForConfigChanges(configFile string) {
 					// TODO: Close the connection?
 				}
 
+				// TODO: vim has a very strange behaviour to save a file. There is
+				// no WRITE event triggered. Instead: RENAME -> CHMOD -> REMOVE is
+				// called on that file and after that, this mechanism lost track of
+				// the file. Why is that tha case? Cant find a valid answer to that.
 				if event.Op&fsnotify.Rename == fsnotify.Rename ||
 					event.Op&fsnotify.Remove == fsnotify.Remove {
 					log.Println("The configuration file is renamed or removed. We cant do any further changes without the config file. So create the file or rename it back and restart the agent.")
@@ -70,6 +95,7 @@ func watchForConfigChanges(configFile string) {
 type argT struct {
 	cli.Helper
 	ConfigFile string `cli:"c,config" usage:"specify a keymap config file"`
+	Device string `cli:"d,device" usage:"specify the serial port, the n3rdpad is hooked to"`
 }
 
 func main() {
@@ -81,12 +107,16 @@ func main() {
 		if args.ConfigFile != "" {
 			configFile = args.ConfigFile
 		}
+		if args.Device == "" {
+			log.Fatal("You need to specify the serial device with the --device parameter.")
+			stop();
+		}
 
 		if !args.Help {
 			// Start up the application
 			log.Println("Using the configuration file", configFile)
-			watchForConfigChanges(configFile)
+			go watchForConfigChanges(configFile)
-			waitAndExecuteCommandsFromDevice()
+			waitAndExecuteCommandsFromDevice(args.Device)
 
 			stop()
 		}