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{$ASMMODE ATT}
{$MODE FPC}
uses
crt,
go32;
const
kbdint = $9;
var
oldint9_handler : tseginfo;
newint9_handler : tseginfo;
clickproc : pointer;
backupDS : Word; external name '___v2prt0_ds_alias';
procedure int9_handler; assembler;
asm
cli
pushl %ds
pushl %es
pushl %fs
pushl %gs
pushal
movw %cs:backupDS, %ax
movw %ax, %ds
movw %ax, %es
movw dosmemselector, %ax
movw %ax, %fs
call *clickproc
popal
popl %gs
popl %fs
popl %es
popl %ds
ljmp %cs:oldint9_handler
end;
procedure int9_dummy; begin end;
procedure clicker;
begin
sound(500); delay(10); nosound;
end;
procedure clicker_dummy; begin end;
procedure install_click;
begin
clickproc := @clicker;
lock_data(clickproc, sizeof(clickproc));
lock_data(dosmemselector, sizeof(dosmemselector));
lock_code(@clicker,
longint(@clicker_dummy) - longint(@clicker));
lock_code(@int9_handler,
longint(@int9_dummy)-longint(@int9_handler));
newint9_handler.offset := @int9_handler;
newint9_handler.segment := get_cs;
get_pm_interrupt(kbdint, oldint9_handler);
set_pm_interrupt(kbdint, newint9_handler);
end;
procedure remove_click;
begin
set_pm_interrupt(kbdint, oldint9_handler);
unlock_data(dosmemselector, sizeof(dosmemselector));
unlock_data(clickproc, sizeof(clickproc));
unlock_code(@clicker,
longint(@clicker_dummy)-longint(@clicker));
unlock_code(@int9_handler,
longint(@int9_dummy)-longint(@int9_handler));
end;
var
ch : char;
begin
install_click;
Writeln('Enter any message. Press return when finished');
while (ch <> #13) do begin
ch := readkey; write(ch);
end;
remove_click;
end.
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