Enables/disables keep alive poll.
#include <sys/inputdd.h>int ioctl (FileDescriptor, KSKAP, Arg)
int FileDescriptor;
uchar * Arg;
The KSKAP ioctl subroutine call enables and disables the keep alive poll. The KSKAP ioctl subroutine call defines the key sequence that the operator can use to kill the process that owns the keyboard. The Arg parameter must point to an array of characters or be equal to NULL. When the Arg parameter points to an array of characters, the first character specifies the number of keys in the sequence. The remainder of the characters in the array define the sequence. Each key of the sequence consists of a position code followed by a modifier flag. The modifier flags can be any combination ok KBDUXSHIFT, KBUXCTRL, and KBDUXALT. If the Arg parameter is equal to NULL, the keep alive poll is disabled. A sequence key count of 0 is invalid.
When the keep alive poll is enabled, a SIGKAP signal is sent to the user process thatregistered the input ring associated with the active channel when the operator presses and holds down the keys in the order specified by the KSKAP ioctl subroutine call. The process must respond with a KSKAPACK ioctl subroutine call within 30 seconds or the keyboard driver issues a SIGKILL signal to terminate the process.
The keep alive poll is controlled on a per-channel basis and defaults to disabled. The KSKAP ioctl subroutine call is not available when the channel is owned by a kernel extension.
| Item | Description |
|---|---|
| FileDescriptor | Specifies the open file descriptor for the keyboard. |
| Arg | Specifies the address of an array of characters or is equal to NULL. |