GIO Special File

AIX Version 4 Files Reference

GIO Special File

Purpose

Provides access to the graphics I/O (GIO) adapter.

Description

The GIO special file is the application interface to the GIO adapter. The GIO special file provides applications with the ability to determine what I/O devices are attached to the GIO adapter.

Configuration

Standard configuration methods are provided for the GIO special file. User configurable attributes for the GIO special file do not exist.

Usage Considerations

The open subroutine call specifying the GIO 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 GIO special file.

Calls to the read and write routines behave as if the call was made to the /dev/null file.

The GIO special file supports the following functions with ioctls:

IOCINFO	Returns the devinfo structure.
GIOQUERYID	Returns the identifier of device connected to the GIO adapter.

Error Codes

The following error codes can be found in the /usr/include/sys/errno.h file:

EFAULT	Indicates insufficient authority to access address or invalid address.
EIO	Indicates an I/O error.
ENOMEM	Indicates insufficient memory for required paging operation.
ENOSPC	Indicates insufficient file system or paging space.
EINVAL	Indicates that an invalid argument was specified.
EINTR	Indicates a request interrupted by signal.
EPERM	Indicates a permanent error occurred.
EBUSY	Indicates the device is busy.
ENXIO	Indicates an unsupported device number.
ENODEV	Indicates an unsupported device or device type mismatch occurred.

Implementation Specifics

The GIO special file is part of Base Operating System (BOS) Runtime.

Files

/usr/include/sys/inputdd.h

Contains the ioctl commands.

Related Information

The close subroutine, ioctl subroutine, open subroutine, read subroutine, write subroutine.

The dials special file, lpfk special file.

Special Files Overview.