Library/VTY

A very simple terminal interface library.

In 150 non-blank non-comment lines of Haskell (and 7 lines of C) vty provides:

Automatic handling of suspend/resume (SIGTSTP+SIGCONT)
Automatic handling of window resizes
Automatic computation of minimal differences
Minimizes repaint area, thus virtually eliminating the flicker problem that plagues ncurses programs
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)
Extensive color scheme support: background colors, default colors, reverse-video, bold, underline, half-bright, and blinking attributes.
Unicode characters on output, automatically setting and resetting UTF-8 mode (beware double width and combining characters!)
Disables ISIG and IXOFF, allowing C-q, C-s, C-c, C-z, and C-\ to be received as input.
Interface is designed for relatively easy compatible extension.

Current disadvantages:

No current support for non-ANSI terminals.
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.

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

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