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void kmain()
{
 initIDT(); //setup an idt
 setinteruptvector(9,kbhandler,0x08,0xEE00);//install an interupt vector -later it will be the keyboard handler
 asm("int $9");//call the interupt
 while(true);//hang
};

//This is my struct for idt entries:
typedef struct interrupt_vector
{
 word handleroffset_l;
 word segmentselector;
 word properties;
 word handleroffset_h;
}intvect;

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intvect* idt;     //Interupt Descriptor Table (global)

inline void initIDT()
{
  unsigned long idtinfo[2]; //this is the info i am going to load into idtr
  int i;
  for(i=0; i<256; i++)setinteruptvector(i,emptyint,0x08,0xEE00);//fill idt with empty ints
  asm("pushfl");//disable ints while loading idt
  idtinfo[0]=(256*(sizeof(intvect)-1))<<16; //size of idt 
  //(i also tried it without '<<16', because some sources do it and others not 
  // i also wonder why one should do that '<<16')
  idtinfo[1]=(unsigned long)idt;            //idt adress
  __asm__ __volatile__ ("lidt (%0)": :"p" (((char *) idtinfo)+2));//load the idt-info stuff
  asm("popfl"); //re-enable ints
};

void setinteruptvector(int tableindex, void *hoffset, word selector, word properties)
//I also tried void(*hoffset)() instead of void* hoffset 
//(and when calling: &kbhandler instead of kbhandler) 
//i have seen both and i think in the end it does the same...(?)
{
  idt[tableindex].segmentselector=selector;
  idt[tableindex].properties=properties;
  idt[tableindex].handleroffset_l=(unsigned short)(((unsigned long)hoffset) & 0xFFFF);
  idt[tableindex].handleroffset_h=(unsigned short)(((unsigned long)hoffset) >>16);
};

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void kbhandler()
{
  //asm ("cli \n");
  kprint("Keyboard input or Coprocessor Overrun Exception!",7);
  while(true);
  //asm("sti \n" "iret \n");
};

void emptyint()
{
 //asm ("cli \n");
 kprint("Empty Interupt!",7);
 while(true);
 //asm("sti \n" "iret \n");
};
//I also tried it with the asm statements not outcommented and the while(true);
//outcommented - same result

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0     16     32     48
+-----+-----+-----+
|limit| base       |
+-----+-----+-----+

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[BITS 32]

;main-program
mov byte [0xB8000], "K"   ;debug-textoutput
mov byte [0xB8001],  4
lidt [idt_pointer]                ;load idtr
mov byte [0xB8002], "!"    ;more textoutput
mov byte [0xB8003],  4

int 0x02                             ;calling an int

hang:
jmp hang


;interrupt descriptor table
idt:
%rep 0xF    ;repeat 16 times the following desc
dw handler ;the adress of the isr 
dw 0x08     ;codesegment-selector
db 0xEE      ;11101110=EE
db 0            ;empty byte
dw 0           ; that would be the end of the adress
%endrep
idt_end:

;idt data to load into idtr
idt_pointer:
dw idt_end-idt-1 ;size
dd idt                  ;adress

;standard-isr to test the idt
handler:
mov byte [0xB8002], "I" ;Output 
mov byte [0xB8003],  4
hng jmp hng                   ;and hang

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mov edi, idt_start
.loop:
mov eax,default_irq_handler ;; this could be relocated by the linker if needed
mov [edi+.descriptor_base_lo],ax
shr eax,16
mov [edi+.descriptor_base_me],al
mov [edi+.descriptor_base_hi],ah
add edi,8
cmp edi,idt_end
jb .loop