cmdmain

Documentation

Index

• Variables
• func Errorf(format string, args ...interface{})
• func Main()
• func RegisterCommand(mode string, makeCmd func(Flags *flag.FlagSet) CommandRunner)
• type CommandRunner
• type UsageError
  • func (ue UsageError) Error() string

Variables

var (
	FlagVersion = flag.Bool("version", false, "show version")
	FlagHelp    = flag.Bool("help", false, "print usage")
	FlagVerbose = flag.Bool("verbose", false, "extra debug logging")
)

var (
	// ExtraFlagRegistration allows to add more flags from
	// other packages (with AddFlags) when Main starts.
	ExtraFlagRegistration = func() {}
	// PreExit is meant to dump additional stats and other
	// verbiage before Main terminates.
	PreExit = func() {}
	// ExitWithFailure determines whether the command exits
	// with a non-zero exit status.
	ExitWithFailure bool
)

var (

	// Indirections for replacement by tests
	Stderr io.Writer = os.Stderr
	Stdout io.Writer = os.Stdout
	Stdin  io.Reader = os.Stdin

	Exit = realExit
)

var ErrUsage = UsageError("invalid command")

Functions

func Errorf

func Errorf(format string, args ...interface{})

Errorf prints to Stderr

func Main

func Main()

Main is meant to be the core of a command that has subcommands (modes), such as camput or camtool.

func RegisterCommand

func RegisterCommand(mode string, makeCmd func(Flags *flag.FlagSet) CommandRunner)

RegisterCommand adds a mode to the list of modes for the main command. It is meant to be called in init() for each subcommand.

Types

type CommandRunner

type CommandRunner interface {
	Usage()
	RunCommand(args []string) error
}

CommandRunner is the type that a command mode should implement.

type UsageError

type UsageError string

func (UsageError) Error

func (ue UsageError) Error() string