The package “exec” was changed a little bit. The following code worked for me.
package main
import (
"fmt"
"os/exec"
)
func main() {
app := "echo"
arg0 := "-e"
arg1 := "Hello world"
arg2 := "\n\tfrom"
arg3 := "golang"
cmd := exec.Command(app, arg0, arg1, arg2, arg3)
stdout, err := cmd.Output()
if err != nil {
fmt.Println(err.Error())
return
}
// Print the output
fmt.Println(string(stdout))
}