Provides access to the natively attached keyboard.
The kbd special file is the interface to the native keyboard. It provides an interface through which applications can receive operator input from the keyboard, control the keyboard LED's, and changing various keyboard parameters. The special file also allows an application to send an audible signal to the operator via the speaker located within the keyboard.
The sound volume, click volume, typematic rate and typematic delay are configurable by the application through the ioctl subroutine. These changes are not reflected in the ODM database. To change these attributes in the ODM database, use the chhwkbd command.
This subroutine call creates a channel between the application and the natively attached keyboard. Two channels are supported. The open subroutine call is processed normally except that the MODE and Oflag parameters are ignored. All keyboard input is flushed until an input ring is established. Only the input ring associated with the most recent open receives input reports.
When the kbd device has been opened twice, input is reported through the input ring registered previous to the first open, after the close subroutine call.
The keyboard device driver does not return nor accept data via read and write. These calls behave as if the call was made to /dev/null. Input data is received from the input drivers via the input ring.
The keyboard device driver
supports the following ioctl commands:
The error codes can be found in
the /usr/include/sys/errno.h file.
The kbd special file is part of Base Operating System (BOS) Runtime.
| /usr/include/sys/inputdd.h | Contains declarations for ioctl commands and input ring report format. |
The close subroutine, ioctl subroutine, open subroutine, read subroutine, write subroutine.