@hackage vty3.0.4

A simple terminal access library

vty is a very simple terminal interface library.

Vty currently provides:

  • Automatic handling of suspend/resume (SIGTSTP+SIGCONT).

  • Automatic handling of window resizes.

  • Supports Unicode characters on output, automatically setting and resetting UTF-8 mode (beware double width and combining characters!)

  • Automatic computation of minimal differences.

  • Minimizes repaint area, thus virtually eliminating the flicker problem that plagues ncurses programs.

  • A pure, compositional interface for efficiently constructing display images.

  • Automatically decodes keyboard keys into (key,[modifier]) tuples.

  • Automatically supports refresh on Ctrl-L.

  • Automatically supports timeout after 50ms for lone ESC (a barely noticable delay)

  • Interface is designed for relatively easy compatible extension.

  • Supports all ANSI SGR-modes (defined in console_codes(4)) with a simple type-safe interface.

  • Properly handles cleanup, leaving the cursor at the bottom of the screen and erasing the last line.

Current disadvantages:

  • No current support for non-ANSI terminals.

  • UTF-8 support only works properly on the linux console/xterm, and even then only if it is not the system default.

  • Minimal support for special keys on terminals other than the linux-console. (F1-5 and arrow keys should work, but anything shifted isn't likely to.)

  • Uses the TIOCGWINSZ ioctl to find the current window size, which appears to be limited to Linux and *BSD.

darcs get --tag=rel-3.0.0 http://code.haskell.org/vty/

To compile the demonstration program: ghc --make Test.hs gwinsz.c

The main documentation consists of the haddock-comments and the demonstration program