From:	Colin w Glenn <cwg01 AT gnofn DOT org>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Interesting Allegro Keyboard Phenomenon...
Date:	Sun, 1 Nov 1998 20:06:02 -0600
Organization:	Greater New Orleans Free-Net
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Message-ID:	<Pine.GSO.3.95.981101200251.5690A-100000@sparkie.gnofn.org>
References:	<71i313$o8b AT nnrp2 DOT farm DOT idt DOT net>
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

Errr, like the SHIFT flag isn't being reset by the program when it exits,
it a BIOS thing, one of those memory locations down under in the low
memory zone.  You MIGHT have to do a little cleaning up and ensure the
CAPS-LOCK flag bit is equal to the state of the CAPS-LOCK led. 

On Sun, 1 Nov 1998, Chia wrote:

->Speculation is welcome.  =)
->
->This pertains to a C++ GUI that I've been developing using Allegro.
->Recently, simple text-fields have been added.
->
->The interesting phenomenon is as follows:
->
->    If you run a program with a textfield in it, and you don't type anything
->in the textfield, dos behaves as normal when the program exits.
->
->    If you run a program with a textfield in it, and you type all lower-case
->stuff in the textfield, when you exit the program dos behaves as normal.
->
->    If you run a program with a textfield in it, and you type any capital
->letters, when you exist dos will have a type of caps-lock enabled.  This
->caps-lock doesn't light the caps-lock light on the keyboard, but it behaves
->just as a caps lock does.  If you type a character w/o shifting, it's in
->uppercase, and if you type it with shifting, it's in lowercase.  Putting the
->real caps-lock on has the effect of making everything normal again.
->
->    This effect also ends if you press the left shift key once.
->
->While this is an interesting effect, I'm wondering how to make it stop.
->Does anyone have any clue what would cause something like this to happen?
->
->Some additional info about my program:
->
->    The GUI is using the Allegro keyboard handlers, so I created a simple
->array to convert ascii letters to Allegro scancodes.
->
->    I also put in a keyboard callback function that would check for the
->[ins] key being pressed so that I could have a global insert/overwrite mode
->flag.
->
->    There are also three #define macros that are as follows:
->
->        #define SHIFT  (key_shifts & KB_SHIFT_FLAG)
->        #define ALT     (key_shifts & KB_ALT_FLAG)
->        #define CTRL   (key_shifts & KB_CTRL_FLAG)
->
->    Which I'm just using to do things like this:
->
->        if (SHIFT) { /* stuff */ }
->
->Thanks!
->
->// chia AT top DOT net -- http://www.top.net/chia/
->
->
->
->

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