package flag
PrintDefaults prints to standard error the default values of all defined command-line flags.
Golang flag.PrintDefaults() function usage example
package main
import (
"flag"
"fmt"
"os"
)
var printHelp bool
var printVerbose string
func setFlags(printHelp *bool) {
flag.BoolVar(printHelp, "help", true, "Print this help message.")
flag.StringVar(&printVerbose, "verbose", "on | off", "Turn verbose mode on or off.")
}
func main() {
setFlags(&printHelp)
flag.Parse()
if printHelp {
fmt.Println("-----------------------------")
flag.PrintDefaults()
fmt.Println("-----------------------------")
os.Exit(0)
}
}
Output :
-----------------------------
-help=true: Print this help message.
-verbose="on | off": Turn verbose mode on or off.
-----------------------------
Reference :
http://golang.org/pkg/flag/#PrintDefaults
