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/*
** Demonstrate TRAPFLAG.ASM
**
** public domain by Bob Stout
*/
#include <stdio.h>
#include <dos.h>
#include <int.h>
extern void ins09(void);
extern void undo09(void);
extern volatile int far ccrcvd;
static void biosprt(char *p)
{
union REGS regs;
while (*p)
{
regs.h.ah = 0x0e; /* Low-level services only! */
regs.h.al = *p++;
regs.x.bx = 0;
int86(0x10, ®s, ®s);
}
}
static void far my_cc(void)
{
char *p1 = "Ctrl-";
char *p2 = "C";
char *p3 = "Break";
char *p4 = " received\r\n";
biosprt(p1);
if (1 == ccrcvd)
biosprt(p2);
else biosprt(p3);
biosprt(p4);
}
main()
{
unsigned seg, ofs;
int ch = 0;
setbuf(stdout, NULL);
my_cc();
ins09();
atexit(undo09);
puts("New Ints 09h & 1Bh installed...");
puts("Hit Esc to quit...");
do
{
if (kbhit())
{
if (0x1b != (ch = getch()))
{
if (0x20 > ch)
{
fputc('^', stdout);
ch += '@';
}
fputc(ch, stdout);
}
}
if (ccrcvd)
{
my_cc();
ccrcvd = 0;
}
} while (0x1b != ch);
}
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