Provides access to the lighted program function key (LPFK) array.
The lpfk special file is the application interface to the lighted program function keys. It allows the application to receive operator input from the LPFKs and to illuminate and darken each key in the array.
Configuration
Standard configuration methods are provided for the lpfk special file. The user cannot enter configurable attributes by way of the command line.
Usage Considerations
open
An open subroutine call specifying the lpfk special file is processed normally except that the Oflag and Mode parameters are ignored. An open request is rejected if the special file is already opened or if a kernel extension attempts to open the lpfk special file. All LPFK inputs are flushed following an open call until an input ring is established.
read and write
The lpfk special file does not support read or write subroutine calls. Instead, input data is obtained from the LPFKs through the input ring. The read and write subroutine calls behave the same as read and write functions of the /dev/null file. See "LFT Input Ring" in AIX® Version 7.1 Kernel Extensions and Device Support Programming Concepts for how to use the input ring.
ioctl
The lpfk special file supports the following ioctl operations:
| Item | Description |
|---|---|
| IOCINFO | Returns the devinfo structure. |
| LPFKREGRING | Registers input ring. |
| LPFKRFLUSH | Flushes input ring. |
| LPFKLIGHT | Sets key lights. |
The error codes can be found in the /usr/include/sys/errno.h file.
| Item | Description |
|---|---|
| EFAULT | Indicates insufficient authority to access address, or invalid address. |
| EIO | Indicates I/O error. |
| ENOMEM | Indicates insufficient memory for required paging operation. |
| ENOSPC | Indicates insufficient file system or paging space. |
| EINVAL | Indicates invalid argument specified. |
| EINTR | Indicates request interrupted by signal. |
| EPERM | Indicates a permanent error occurred. |
| EBUSY | Indicates device busy. |
| ENXIO | Indicates unsupported device number. |
| ENODEV | Indicates unsupported device, or device type mismatch. |
| Item | Description |
|---|---|
| /usr/include/sys/inputdd.h | Contains declarations for ioctl commands and input ring report format |