set up return codes

listen.go

@@ -313,8 +313,9 @@ func startMessage(l Listen) {
 	}
 }
 
-func (l Listen) Run() {
+func (l Listen) Run() int {
 	// catch ^C
+	ret := 0
 	quit := make(chan bool)
 	c := make(chan os.Signal, 1)
 	signal.Notify(c, os.Interrupt)
@@ -344,6 +345,7 @@ func (l Listen) Run() {
 		for {
 			if !triggered {
 				fmt.Println()
+				ret = 130
 				break
 			}
 			<-c
@@ -355,4 +357,5 @@ func (l Listen) Run() {
 		printStatus("& Exiting...\n")
 	}
 
+	return ret
 }

main.go

@@ -66,7 +66,7 @@ func validateArgs(opts Options, commandLen int) error {
 	return nil
 }
 
-func setup(opts Options, command []string) {
+func setup(opts Options, command []string) int {
 	var filesMap map[string]bool = make(map[string]bool)
 	var cksumMap map[string][]byte = make(map[string][]byte)
 	var intervalMap map[string]time.Time = make(map[string]time.Time)
@@ -104,11 +104,14 @@ func setup(opts Options, command []string) {
 
 	if success {
 		l := Listen{filesMap, cksumMap, intervalMap, opts.Condition, opts.NoChecksum, intervalDuration, command, opts.Quiet, opts.RunFirst}
-		l.Run()
+		return l.Run()
 	}
+
+	return -1
 }
 
 func main() {
+	ret := 0
 	opts := Options{}
 	parser := flags.NewParser(&opts, flags.Default)
 	parser.Usage = "[OPTIONS] -- [COMMAND]"
@@ -116,8 +119,12 @@ func main() {
 
 	defer func() {
 		if err := recover(); err != nil {
-			fmt.Fprintf(os.Stderr, "%s\n", err)
-			os.Exit(1)
+			switch ret {
+			case -1:
+				os.Exit(5)
+			default:
+				os.Exit(ret)
+			}
 		}
 	}()
 
@@ -125,7 +132,10 @@ func main() {
 		if opts.Version {
 			fmt.Printf("listen %s\n", VERSION)
 		} else if err := validateArgs(opts, len(remaining)); err == nil {
-			setup(opts, remaining)
+			ret = setup(opts, remaining)
+			if ret != 0 {
+				panic(ret)
+			}
 		}
 	}