From: Erik Rull <erik_rull AT bluewin DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Still problems with protected_mode_int
Date: Thu, 13 Jan 2000 17:44:31 +0100
Organization: tesion Communikationsnetze Suedwest GmBH & Co.KG, Stuttgart, Germany
Lines: 68
Message-ID: <387E00EF.58796444@bluewin.de>
NNTP-Posting-Host: stu1ir8-101-92.ras.tesion.net
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-Mailer: Mozilla 4.6 [de]C-CCK-MCD QXW03207  (Win95; I)
X-Accept-Language: de,en
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

Hi,

I've read your Mails about my problem, and I've changed it as good as
possible.
But it still remains.
First: In plain DOS, the ISR isn't called, but every other things work
(the system() call). With printf() and cout <<... nothing appears.
Then in W95 in a DOS - Box: The ISR is called and outputs the ++tics,
and it's the same result when I use printf() or cout <<...
When the getkey() is passed, windows returns with the following message:

Error at: 0028:C003D8B6
V86MMGR(01)+0000006A
IRQ:0 (no "blue screen")
?????
And the system hangs up...

What I finally want to achieve is, that the interrupt routine continues,
when the other programm runs. But I don't think, that there's a good
solution.


#include <pc.h>
#include <dpmi.h>
#include <stdio.h>
#include <iostream.h>

     volatile int tics = 0;

     void timer_handler()
     {
      cout << "Tics passed: " << ++tics << "\n";
     }

     int main()
     {

     lock(timer_handler);  // I don't know, if it's right. The error
occurs with and without it!!!

       _go32_dpmi_seginfo old_handler, new_handler;

       _go32_dpmi_get_protected_mode_interrupt_vector(8, &old_handler);

       new_handler.pm_offset = (int) timer_handler;
       new_handler.pm_selector = _go32_my_cs();
       _go32_dpmi_chain_protected_mode_interrupt_vector(8,
&new_handler);
       getkey();
       cout << "Running \"system()\"\n";
       system("timer3.exe");

       _go32_dpmi_set_protected_mode_interrupt_vector(8, &old_handler);
        cout << tics;
       return 0;
     }


programm called by system():

#include <iostream.h>

int main()
{
    cout << "timer3.exe is running\n";
}