Re: about keycodes

[Thomas Dickey]

On Tue, 29 May 2007, chinlu chinawa wrote:

> I've been trying to find out how does curses do so the
> keystroke-getting mechanism bypasses endianness
> issues.

curses reads a stream of characters (and there should be no endianess
or byte-ordering issues in that).

> I've been trying to make some sense out of this, for
> example perhaps values on the fifo were summed, and/or
> then (un)mettaed ((x) & (~0x80)), or (un)controlled as
> keycodes seem to start over 256 decimal (MIN_KEY 0401)
> have tried different things, though I don't seem to
> get how it "magically" knows the keypress was
> key_left.

It's matching strings - they're stored in a tree to make the matching
somewhat more efficient than a list.  As soon as it finds a match,
curses returns the corresponding keycode.

--
Thomas E. Dickey
http://invisible-island.net
ftp://invisible-island.net