Date: Sun, 2 Apr 2000 09:46:40 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Jonathan Meunier <jonathanm AT corel DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: keyboard interrupt
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On Mon, 27 Mar 2000, Jonathan Meunier wrote:

> void install_keyboard() {
>   if(kb_installed == TRUE)
>     return;
> 
>   new_kb_seginfo.pm_offset = (int)new_keyboard_int;
>   new_kb_seginfo.pm_selector = _go32_my_cs();
> 
>   kb_installed = TRUE;
> 
>   _go32_dpmi_get_protected_mode_interrupt_vector(0x09, &old_kb_seginfo);
>   _go32_dpmi_allocate_iret_wrapper(&new_kb_seginfo);
>   _go32_dpmi_set_protected_mode_interrupt_vector(0x09, &new_kb_seginfo);
> }

Beware: this code doesn't lock the code and data used inside the
interrupt handler.  So it will most probably crash, especially on
memory-starved systems.

I suggest to read section 18.9 of the FAQ for more details.