terminal

Documentation

Overview

Package terminal provides support functions for dealing with terminals, as commonly found on UNIX systems.

Putting a terminal into raw mode is the most common requirement:

oldState, err := terminal.MakeRaw(0)
if err != nil {
        panic(err)
}
defer terminal.Restore(0, oldState)

Index

• func GetSize(fd int) (width, height int, err error)
• func IsTerminal(fd int) bool
• func ReadPassword(fd int) ([]byte, error)
• func Restore(fd int, state *State) error
• type EscapeCodes
• type State
  • func MakeRaw(fd int) (*State, error)
• type Terminal
  • func NewTerminal(c io.ReadWriter, prompt string) *Terminal
  • func (t *Terminal) ReadLine() (line string, err error)
  • func (t *Terminal) ReadPassword(prompt string) (line string, err error)
  • func (t *Terminal) SetPrompt(prompt string)
  • func (t *Terminal) SetSize(width, height int)
  • func (t *Terminal) Write(buf []byte) (n int, err error)

Functions

func GetSize

func GetSize(fd int) (width, height int, err error)

GetSize returns the dimensions of the given terminal.

func IsTerminal

func IsTerminal(fd int) bool

IsTerminal returns true if the given file descriptor is a terminal.

func ReadPassword

func ReadPassword(fd int) ([]byte, error)

ReadPassword reads a line of input from a terminal without local echo. This is commonly used for inputting passwords and other sensitive data. The slice returned does not include the \n.

func Restore

func Restore(fd int, state *State) error

Restore restores the terminal connected to the given file descriptor to a previous state.

Types

type EscapeCodes

type EscapeCodes struct {
	// Foreground colors
	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte

	// Reset all attributes
	Reset []byte
}

EscapeCodes contains escape sequences that can be written to the terminal in order to achieve different styles of text.

type State

type State struct {
	// contains filtered or unexported fields
}

State contains the state of a terminal.

func MakeRaw

func MakeRaw(fd int) (*State, error)

MakeRaw put the terminal connected to the given file descriptor into raw mode and returns the previous state of the terminal so that it can be restored.

type Terminal

type Terminal struct {
	// AutoCompleteCallback, if non-null, is called for each keypress
	// with the full input line and the current position of the cursor.
	// If it returns a nil newLine, the key press is processed normally.
	// Otherwise it returns a replacement line and the new cursor position.
	AutoCompleteCallback func(line []byte, pos, key int) (newLine []byte, newPos int)

	// Escape contains a pointer to the escape codes for this terminal.
	// It's always a valid pointer, although the escape codes themselves
	// may be empty if the terminal doesn't support them.
	Escape *EscapeCodes
	// contains filtered or unexported fields
}

Terminal contains the state for running a VT100 terminal that is capable of reading lines of input.

func NewTerminal

func NewTerminal(c io.ReadWriter, prompt string) *Terminal

NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is a local terminal, that terminal must first have been put into raw mode. prompt is a string that is written at the start of each input line (i.e. "> ").

func (*Terminal) ReadLine

func (t *Terminal) ReadLine() (line string, err error)

ReadLine returns a line of input from the terminal.

func (*Terminal) ReadPassword

func (t *Terminal) ReadPassword(prompt string) (line string, err error)

ReadPassword temporarily changes the prompt and reads a password, without echo, from the terminal.

func (*Terminal) SetPrompt

func (t *Terminal) SetPrompt(prompt string)

SetPrompt sets the prompt to be used when reading subsequent lines.

func (*Terminal) SetSize

func (t *Terminal) SetSize(width, height int)

func (*Terminal) Write

func (t *Terminal) Write(buf []byte) (n int, err error)