Помогите разобраться в не большом коде *.CPP

#include <conio.h>
#include <stdlib.h>
#include <stdio.h>
#include <dos.h>
const int N = 5;
const int sDELAY=1500;
const int lDELAY=3000;
struct Registers
{
    unsigned int  BP;
    unsigned int  DI;
    unsigned int  SI;
    unsigned int  DS;
    unsigned int  ES;
    unsigned int  DX;
    unsigned int  CX;
    unsigned int  BX;
    unsigned int  AX;
    unsigned int  IP;
    unsigned int  CS;
    unsigned int  FLAGS;
};
struct context
{
    unsigned int SP;
    unsigned int bloat[1000];
    Registers regs;
    char state;
};
context fils[N];
int vilki[N];
int curfil = -1;
unsigned int old_SP;
int Quit = 0;
void interrupt (*oldvect )(...);
void interrupt NewTimer(...);
void filosof();
void prtstatus();
void main()
{
    for (int i = 0; i < N; i++)
    {
        fils[i].SP = FP_OFF( &fils[i].regs.BP );
        fils[i].regs.IP = FP_OFF(filosof);
        fils[i].regs.CS = _CS;
        fils[i].regs.DS = _DS;
        fils[i].regs.ES = _ES;
        fils[i].regs.FLAGS = _FLAGS;
        vilki[i] = 0;
        fils[i].state = 0;
    }
    oldvect = getvect(0x8);
    setvect(0x8, NewTimer);
    while(Quit != 1);
    setvect(0x8, oldvect);
    getchar();
}
void interrupt NewTimer(...)
{
    disable();
    oldvect();
    if (kbhit())
        Quit = 1;
    if (curfil<0)
        old_SP = _SP;
    else
        fils[curfil].SP = _SP;
    if (curfil+1 >= N)
        curfil = 0;
    else
        curfil+=1;
    prtstatus();
    if (Quit)
        _SP = old_SP;
    else
        _SP = fils[curfil].SP;
    enable();
}
void filosof()
{
     int f1, f2;
     if (curfil == 0)
     {
        f1 = N - 1;
        f2 = 0;
     }
     else
     {
        f1 = curfil -1;
        f2 = curfil;
     }
    while(1)
    {
      if (vilki[f1]==0 && vilki[f2]==0)
      {
        //delay(random(sDELAY));
        vilki[f1] = 1;
        vilki[f2] = 1;
        fils[curfil].state = 2;
        delay(random(sDELAY));
        vilki[f1] = 0;
        vilki[f2] = 0;
        fils[curfil].state = 1;
        delay(random(sDELAY));
      }
      else
      {
          fils[curfil].state = 0;
          delay(random(lDELAY));
      }
    }
}
void prtstatus()
{
   int i;
    printf("*****************************************\n");
    for (i=0; i<N; i++)
        printf("filosof #%d : %d \n",i,fils[i].state);
    for (i=0; i<N; i++)
        printf("vilka #%d : %d \n",i,vilki[i]);
    printf("*****************************************\n");
}

if (kbhit())
   Quit = 1;

        fils[i].SP = FP_OFF( &fils[i].regs.BP );
        fils[i].regs.IP = FP_OFF(filosof);