Tests the status of the Shift, Alt, Ctrl and Lock keys.
Note: This routine is supported for native COBOL only.
Syntax:
call X"B0" using function-code
status-block
Parameters:
-
function-code
- Call prototype: cblt-x1-compx
- Picture: pic x comp-x.
-
status-block
- Group containing:
01 status-block
03 status-inds pic x *> pic x
03 status-id cblt-x1-compx *> pic x comp-x.
03 status-res pic x(6) *> pic x(6)
On Entry:
-
function-code
- Value 2.
-
status-id
- Must be set to 2. It is overwritten by the call, so must be reset to 2 before each call.
-
status-res
- Reserved.
On Exit:
-
status-inds
- Contains bit settings indicating the status of the keys (1=key pressed, 0=key not pressed) in the following order:
| bit 7
|
Ins
|
| bit 6
|
Caps Lock
|
| bit 5
|
Num Lock
|
| bit 4
|
Scroll Lock
|
| bit 3
|
Alt
|
| bit 2
|
Ctrl
|
| bit 1
|
Shift (left key only)
|
| bit 0
|
Shift (right key only)
|
Comments:
For the Alt, Ctrl and Shift keys, the routine returns a 1 only if the key is actually pressed when the routine is called; for the other keys, the relevant bit is alternately set and unset each time the key is pressed.
Effective use of function 2 requires that the call is repeated at very frequent intervals.