The dials special file is the application interface to the dials. It allows the applications to receive operator input from the dials and to set the granularity of the dials.
Standard configuration methods are provided for the dials special file. The user cannot enter configurable attributes by way of the command line.
An open subroutine call specifying the dials 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 dials special file. All dials inputs are flushed following an open call until an input ring is established.
The dials special file does not support read or write subroutine calls. Input data is obtained from the dials via the input ring. The read and write subroutine calls behave the same as read or write to /dev/null. See "LFT Input Ring" in AIX 5L Version 5.1 Kernel Extensions and Device Support Programming Concepts for how to use the input ring.
The dials special file supports
the following ioctl operations:
| IOCINFO | Returns the devinfo structure. |
| DIALREGRING | Registers input ring. |
| DIALRFLUSH | Flushes input ring. |
| DIALSETGRAND | Sets dial granularity. |
The error codes can be found in
the /usr/include/sys/errno.h file.
The dials 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 GIO special file, kbd special file, lpfk special file, mouse special file, tablet special file.
The close subroutine, ioctl subroutine, open subroutine, read subroutine, write subroutine.
Graphic Input Devices Subsystem Overview in AIX 5L Version 5.1 Kernel Extensions and Device Support Programming Concepts.