Add remaining

spawn/spawn.go

@@ -0,0 +1,55 @@
+package spawn
+
+import (
+	"fmt"
+	"io"
+	"os/exec"
+)
+
+func Spawn() {
+	// Cmd object represents the external process
+	dateCmd := exec.Command("date")
+
+	// Runs and wait for it to finish, output collected
+	dateOut, err := dateCmd.Output()
+
+	if err != nil {
+		panic(err)
+	}
+
+	fmt.Println("> date")
+	fmt.Println(string(dateOut))
+
+	_, err = exec.Command("date", "-x").Output()
+	if err != nil {
+		switch e := err.(type) {
+		case *exec.Error:
+			fmt.Println("failed executing:", err)
+		case *exec.ExitError:
+			fmt.Println("command exit code:", e.ExitCode())
+		default:
+			panic(err)
+		}
+	}
+
+	grepCmd := exec.Command("grep", "hello")
+
+	grepIn, _ := grepCmd.StdinPipe()
+	grepOut, _ := grepCmd.StdoutPipe()
+	grepCmd.Start()
+	grepIn.Write([]byte("hello world\ngoodbye grep\nI am Jin, hello"))
+	grepIn.Close()
+	grepBytes, _ := io.ReadAll(grepOut)
+	grepCmd.Wait()
+
+	fmt.Println("> grep hello")
+	fmt.Println(string(grepBytes))
+
+	lsCmd := exec.Command("bash", "-c", "ls -a -l -h")
+	lsOut, err := lsCmd.Output()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println("> ls -a -l -h")
+	fmt.Println(string(lsOut))
+}