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From: rg@msel.unh.edu (Roger Gonzalez)
Newsgroups: comp.sys.ibm.pc.misc,comp.os.msdos.programmer
Subject: help!  dos(?) is grabbing half my alt keys
Message-ID: <1991Jan7.230518.25949@uunet!unhd>
Date: 7 Jan 91 23:05:18 GMT
Distribution: comp
Organization: UNH Marine Systems Engineering Laboratory
Lines: 45

In Turbo C++ version 1.0:

#include <conio.h>
#include <stdio.h>
main()
{
    int c, done;

    done = 0;
    printf("Hit a key, <esc> to quit\n");
    while (!done) {
        c = getch();
        printf("keyboard scan code 0x%02x\n", c);
        if (c == 27)
            done = 1;
    }
}

Simple, right?

Why is it that the second half of the 2 byte sequence transmitted by
certain alt keys sometimes gets absorbed and used by DOS?  For example,
<alt>R transmits the sequence 0x00 0x13.  Every now and then, the output
will get hung as if the 0x13 (which is ^S) was typed:
keyboard sc

Also, <alt>Q, which transmits 0x00 0x10 uses the 0x10 as the ^P and
turns on parallel printer echoing.

There are probably others that do magic things as well.
Borland's tech support said to grab some vector or another;  I haven't 
looked into this avenue yet because it seems like an overkill solution
to a simple problem.  

Please help me!  This was supposed to be quick and dirty!
(email if possible)


-Roger
 (a unix programmer serving time in dosland)
-- 
"The question of whether a computer can think is no more interesting
 than the question of whether a submarine can swim" - Edsgar W. Dijkstra 
rg@[msel|unhd].unh.edu        |  UNH Marine Systems Engineering Laboratory
r_gonzalez@unhh.bitnet        |  Durham, NH  03824-3525