go parse opt args
package main
import "flag"
import "fmt"
func main() {
wordPtr := flag.String("word", "foo", "a string")
numbPtr := flag.Int("numb", 42, "an int")
boolPtr := flag.Bool("fork", false, "a bool")
var svar string
flag.StringVar(&svar, "svar", "bar", "a string var")
flag.Parse()
fmt.Println("word:", *wordPtr)
fmt.Println("numb:", *numbPtr)
fmt.Println("fork:", *boolPtr)
fmt.Println("svar:", svar)
fmt.Println("tail:", flag.Args())
}