Adds version flag

main.go

@@ -1,11 +1,17 @@
 package main
 
 import (
+	"fmt"
 	"math"
+	"os"
 	"runtime"
 	"sync"
 )
 
+const version = "v1.0.1"
+
+const usage = "heat [-v|--verbose]"
+
 func heat() {
 	var t float64 = math.MaxFloat64
 	for {
@@ -17,6 +23,15 @@ func heat() {
 }
 
 func main() {
+	if len(os.Args) > 1 {
+		if verbose(os.Args) {
+			fmt.Printf("heat version %v\n", version)
+			os.Exit(0)
+		} else {
+			fmt.Fprintf(os.Stderr, "usage: %v\n", usage)
+			os.Exit(1)
+		}
+	}
 	wg := sync.WaitGroup{}
 	wg.Add(1)
 	for i := 0; i < runtime.NumCPU(); i++ {
@@ -24,3 +39,14 @@ func main() {
 	}
 	wg.Wait()
 }
+
+func verbose(args []string) bool {
+	r := false
+	for _, arg := range args {
+		switch arg {
+		case "-v", "-version", "--version", "v", "version":
+			r = true
+		}
+	}
+	return r
+}