package flag
PrintDefaults prints, to standard error unless configured otherwise, the default values of all defined flags in the set.
Golang flag.FlagSet.PrintDefaults() function usage example
package main
import (
"flag"
"fmt"
)
var flagSet *flag.FlagSet
func main() {
flagSet = flag.NewFlagSet("example", flag.ContinueOnError)
flagSet.String("file", "", "filename to view")
flagSet.Int("timeout", 5000, "specify the time in milliseconds to wait for a response")
err := flagSet.Parse([]string{"file", "timeout"})
if err != nil {
fmt.Println(err)
}
flagSet.PrintDefaults()
}
Output :
-file="": filename to view
-timeout=5000: specify the time in milliseconds to wait for a response
Reference :
http://golang.org/pkg/flag/#FlagSet.PrintDefaults
