About Device I/O Control

Applications typically use the IOCTL interface to carry out selected Microsoft® MS-DOS® system functions, to obtain information about a device, or to carry out input and output (I/O) operations that are not available through standard Win32 functions.

The following topics describe the device IOCTL interface, explain how to use the interface in applications, and describe how to implement the interface in virtual devices (VxDs).

• Input and Output Control in Applications
• Asynchronous Operations and VxDs
• Using VWIN32 to Carry Out MS-DOS Functions
• Supporting Input-Output Control in VxDs
• Device I/O Control Reference

For information about the device IOCTL interface for other operating systems that support the Win32 API, see Device Input and Output.