termstatus

Documentation

Index

• func CanUpdateStatus(fd uintptr) bool
• func IsProcessBackground(fd uintptr) bool
• func Quote(line string) string
• func Truncate(s string, w int) string
• func WrapStdio(term *Terminal) (stdout, stderr io.WriteCloser)
• type Terminal
  • func New(wr io.Writer, errWriter io.Writer, disableStatus bool) *Terminal
  • func (t *Terminal) CanUpdateStatus() bool
  • func (t *Terminal) Error(line string)
  • func (t *Terminal) Print(line string)
  • func (t *Terminal) Run(ctx context.Context)
  • func (t *Terminal) SetStatus(lines []string)

Functions

func CanUpdateStatus

func CanUpdateStatus(fd uintptr) bool

CanUpdateStatus returns true if status lines can be printed, the process output is not redirected to a file or pipe.

func IsProcessBackground

func IsProcessBackground(fd uintptr) bool

IsProcessBackground reports whether the current process is running in the background. fd must be a file descriptor for the terminal.

func Quote

func Quote(line string) string

Quote lines with funny characters in them, meaning control chars, newlines, tabs, anything else non-printable and invalid UTF-8.

This is intended to produce a string that does not mess up the terminal rather than produce an unambiguous quoted string.

func Truncate

func Truncate(s string, w int) string

Truncate s to fit in width (number of terminal cells) w. If w is negative, returns the empty string.

func WrapStdio

func WrapStdio(term *Terminal) (stdout, stderr io.WriteCloser)

WrapStdio returns line-buffering replacements for os.Stdout and os.Stderr. On Close, the remaining bytes are written, followed by a line break.

Types

type Terminal

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

Terminal is used to write messages and display status lines which can be updated. When the output is redirected to a file, the status lines are not printed.

func New

func New(wr io.Writer, errWriter io.Writer, disableStatus bool) *Terminal

New returns a new Terminal for wr. A goroutine is started to update the terminal. It is terminated when ctx is cancelled. When wr is redirected to a file (e.g. via shell output redirection) or is just an io.Writer (not the open *os.File for stdout), no status lines are printed. The status lines and normal output (via Print/Printf) are written to wr, error messages are written to errWriter. If disableStatus is set to true, no status messages are printed even if the terminal supports it.

func (*Terminal) CanUpdateStatus

func (t *Terminal) CanUpdateStatus() bool

CanUpdateStatus return whether the status output is updated in place.

func (*Terminal) Error

func (t *Terminal) Error(line string)

Error writes an error to the terminal.

func (*Terminal) Print

func (t *Terminal) Print(line string)

Print writes a line to the terminal.

func (*Terminal) Run

func (t *Terminal) Run(ctx context.Context)

Run updates the screen. It should be run in a separate goroutine. When ctx is cancelled, the status lines are cleanly removed.

func (*Terminal) SetStatus

func (t *Terminal) SetStatus(lines []string)

SetStatus updates the status lines. The lines should not contain newlines; this method adds them. Pass nil or an empty array to remove the status lines.