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IQueueCallbackRead interface (wudfddi.h)

  • Article

[Warning: UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2. For more info, see Getting Started with UMDF.]

An I/O queue notifies a driver when a read request is available for the driver. The I/O queue notifies the driver when an application calls the Microsoft Win32 ReadFile or ReadFileEx function. The driver can handle the notification by registering the IQueueCallbackRead interface.

Inheritance

The IQueueCallbackRead interface inherits from the IUnknown interface. IQueueCallbackRead also has these types of members:

  • Methods

Methods

The IQueueCallbackRead interface has these methods.

 
IQueueCallbackRead::OnRead

The OnRead method is called to handle a read request when an application reads information from a device through the Microsoft Win32 ReadFile or ReadFileEx function.

Remarks

A driver registers the IQueueCallbackRead interface when it calls the IWDFDevice::CreateIoQueue method to create an I/O queue or to configure the default I/O queue. For more information about creating or configuring an I/O queue, see Configuring Dispatch Mode for an I/O Queue.

Requirements

Requirement Value
Target Platform Windows
Header wudfddi.h