INT 15h,  4Fh (79)       Keyboard Intercept                              many

Called by the hardware keyboard handler (INT 09h), allowing the
replacement or removal of a key.

On entry:      AH         4Fh
AL         Scan code

Returns:       Carry      Cleared if scan code removed, else set
AL         New scan code if changed, else original scan


Upon entry to this service, AL will contain the scan code of the
keystroke. If the user wishes to change the scan code, put the new
scan code in AL and set the Carry Flag. If the scan code is to remain
the same, then leave AL alone and set the Carry Flag. The user can
remove or ignore the keystroke by returning with the Carry Flag clear.

Notes:         This service is not available for the PC, PCjr, XT
dated 11/08/82, and the AT dated 1/10/84.

By writing a handler for this service, the user can
change the meaning of a key. The operating system
normally will return the scan code unchanged (that
is, it will leave AL alone and return with the Carry
Flag set).

To determine the machines that support this feature,
see Service C0h (Return System Configuration).

See also: INT 15h, C0h
See also: INT 09h

INT 15h, 4Fh (79) Keyboard Intercept many