vt100

VT100

• Supports colors and attributes.
• Supports platforms with VT100 support and a /dev/tty device.
• Can detect the terminal size.
• Can get key-presses, including arrow keys (252, 253, 254, 255).
• Has a Canvas struct, for drawing only the updated lines to the terminal.
• Uses the spec directly, but memoizes the commands sent to the terminal, for speed.
• Could be used for building a better dialog or whiptail utility.

Editor

For an editor that uses this module, take a look at o.

Images

Screen recording of the shooter example, where you can control a small character with the arrow keys and shoot with space.

Screen recording of the menu example, which uses VT100 terminal codes and demonstrates a working menu.

A physical VT100 terminal. Photo by Jason Scott, CC BY 2.0

The vt100 Go Module

Requires Go 1.10 or later.

Features and limitations

• Can detect letters, arrow keys and space. F12 and similar keys are not supported (they are supported by vt220 but not vt100).
• Resizing the terminal when using the Canvas struct may cause artifacts, for a brief moment.
• Holding down a key may trigger key repetition which may speed up the main loop.

Simple use

Output "hi" in blue:

vt100.Blue.Output("hi")

Erase the current line:

vt100.Do("Erase Line")

Move the cursor 3 steps up (it's a bit verbose, but it's generated directly from spec, memoized for speed and is easy to wrap in a custom function):

vt100.Set("Cursor Up", map[string]string{"{COUNT}": "3"})

The full overview of possible commands are at the top of vt100.go.

Another example

See cmd/move for a more advanced example, where a character can be moved around with the arrow keys.

A small editor using vt100

The o editor that uses vt100 can be used for editing ie. Go, Bash or C++ code. Quick installation:

go get -u github.com/xyproto/o

General info

• Version: 1.9.11
• Licence: BSD
• Author: Alexander F. Rødseth <xyproto@archlinux.org>