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IOUserClient.h

Overview

This header contains the class definition of the IOUserClient class. This class defines methods that support the communication between user-space device drivers and the kernel. For more information, see I/O Kit Fundamentals and Accessing Hardware From Applications.

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Classes

IOUserClient

Provides a basis for communication between client applications and I/O Kit objects.

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Enumerations

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kIOExternalMethodScalarInputCountMax

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Constants to specify the maximum number of scalar arguments in the IOExternalMethodArguments structure. These constants are documentary since the scalarInputCount, scalarOutputCount fields reflect the actual number passed.

enum { 
    kIOExternalMethodScalarInputCountMax = 16, 
    kIOExternalMethodScalarOutputCountMax = 16, 
};  

Constants

kIOExternalMethodScalarInputCountMax

The maximum number of scalars able to passed on input.

kIOExternalMethodScalarOutputCountMax

The maximum number of scalars able to passed on output.

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kIOUCVariableStructureSize

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Constant to denote a variable length structure argument to IOUserClient.

enum { 
    kIOUCVariableStructureSize = 0xffffffff 
};  

Constants

kIOUCVariableStructureSize

Use in the structures IOExternalMethod, IOExternalAsyncMethod, IOExternalMethodDispatch to specify the size of the structure is variable.

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Last Updated: 2008-12-19