Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!purdue!haven!adm!news
From: CDCKAB%EMUVM1.BITNET@cunyvm.cuny.edu ( Karl Brendel)
Newsgroups: comp.lang.pascal
Subject: (R)Scan codes in TurboPascal
Message-ID: <24528@adm.BRL.MIL>
Date: 17 Sep 90 15:35:38 GMT
Sender: news@adm.BRL.MIL
Lines: 35


In article <1561.26f20a24@waikato.ac.nz>,
  Ian McDonald <iam@waikato.ac.nz> asks

>How do you pick up Scan codes in TP 5.5?  From my reading of the manuals
>you have to resort to machine code.  I am after picking up Ctrl-ESC as
>well as just Esc as ReadKey doesn't differentiate.

I've been using TurboPower's libraries for so long now that my immediate
reflex was to tell you to call ReadKeyWord. However, if you don't use
TurboProfessional or ObjectProfessional, and you are interested in
picking up scan codes for keys that return characters <> #0 (CRT.ReadKey
can return scan codes for those keys which return #0), then the general
solution is to call INT $16 directly, with AH=0.

Now for the bad news: Ctrl-Esc is _never_ going to return anything
different than plain Esc. Esc is ^[, and you are asking the system to
distinguish between that and ^^[. It won't. The best you can hope for is
to read the state of the shift keys when you call ReadKey or your INT
$16 routine. Other replies have shown how to do that, and have pointed
out that the shift state you determine will be that at the time of the
call and not necessarily the one corresponding to the keypress that fed
ReadKey or your INT $16 routine.

The only way I see for you to accomplish your goal is to write your own
keyboard handler so you can determine the shift state _at the time of
the keypress_ and flag the keypresses of interest somehow.

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