how to capture CTRL, SHIFT and ALT ?

CTRL SHIFT and ALT ?
They have no ascii or extended ascii, how to capture?
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what's this below? another way of capture keys? how to?
#define SHIFT_R 0x0001
#define SHIFT_L 0x0002
#define CTRL 0x0004
#define ALT 0x0008
#define SCROLL_LOCK_ON 0x0010
#define NUM_LOCK_ON 0x0020
#define CAPS_LOCK_ON 0x0040


appreciate.

Try searching for it on this board.

The main theme you'll find is that you won't be able to without pulling your hair out.

ok,thx.

what's this below? another way of capture keys? how to?
#define SHIFT_R 0x0001
#define SHIFT_L 0x0002
#define CTRL 0x0004
#define ALT 0x0008
#define SCROLL_LOCK_ON 0x0010
#define NUM_LOCK_ON 0x0020
#define CAPS_LOCK_ON 0x0040

I havent played with this much myself, but I think what it means is that you're dealing with a sequence of 2 characters.

After you receive 0x00, 0x01 would mean that SHIFT_R has been pressed.