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From: meissner@osf.org (Michael Meissner)
Newsgroups: comp.unix.questions
Subject: Re: Curses and the arrow keys
Message-ID: <MEISSNER.90Aug26173207@osf.osf.org>
Date: 26 Aug 90 21:32:07 GMT
References: <1990Aug24.175453.4310@irscscm.UUCP>
Sender: news@OSF.ORG
Organization: Open Software Foundation
Lines: 54
In-reply-to: mlake@irscscm.UUCP's message of 24 Aug 90 17:54:53 GMT

In article <1990Aug24.175453.4310@irscscm.UUCP> mlake@irscscm.UUCP
(Marshall Lake) writes:

| I am writing a program which will be taking advantage of curses.  I am
| trying to utilize the arrow keys and am confused (actually all of
| curses confuses me).  I am doing a getch () and if I get an ESCAPE I do
| another getch ().  If I addch () for each character I get (the ESCAPE
| and the next character) then the cursor moves around properly on the
| screen but the x/y coordinates in the window structure do not follow
| suit.  Curses is recognizing the arrow keys simply as regular
| characters.  Am I naive in thinking that curses is smart enough to
| handle the arrow keys specially?  Should I be moving the cursor
| manually via the move function?

If your curses is based on the System V.2 curses, it will have a
'keypad' function which turns on recognizing any arrow keys or
function keys.  Here is a copy of the documentation:


     NAME
          keypad - enable keypad

     SYNTAX
          keypad(win, bf)
          WINDOW *win;
          bool bf;

     DESCRIPTION
	  This option enables the keypad of the user's terminal.  If
          the keypad is enabled, pressing a function key (such as an
          arrow key) will return a single value representing the
          function key.  For example, pressing the left arrow key
          results in the value KEY_LEFT being returned..  For more
          information see the Guide to Curses Screen-Handling.  The
          routine is used to return the character.  If the keypad is
          disabled, does not treat function keys as special keys and
          the program interprets the escape sequences itself.  Keypad
          layout is terminal dependent; some terminals do not even
          have a keypad.

     SEE ALSO
          getch(3cur)
          Guide to Curses Screen-Handling

Note that KEY_LEFT and friends will not fit in an ordinary character,
so make sure getch's result is stored in an int.

If your curses is still based on the Berkeley curses, you have my
sympathies.  This is one area where System V is better than BSD.
--
Michael Meissner	email: meissner@osf.org		phone: 617-621-8861
Open Software Foundation, 11 Cambridge Center, Cambridge, MA, 02142

Do apple growers tell their kids money doesn't grow on bushes?