IDebugDataSpaces::ReadIo method

The ReadIo method reads from the system and bus I/O memory.


  [in]             ULONG InterfaceType,
  [in]             ULONG BusNumber,
  [in]             ULONG AddressSpace,
  [in]             ULONG64 Offset,
  [out]            PVOID Buffer,
  [in]             ULONG BufferSize,
  [out, optional]  PULONG BytesRead


InterfaceType [in]

Specifies the interface type of the I/O bus. This parameter may take values in the INTERFACE_TYPE enumeration defined in wdm.h.

BusNumber [in]

Specifies the system-assigned number of the bus. This is usually zero, unless the system has more than one bus of the same interface type.

AddressSpace [in]

This parameter must be equal to one.

Offset [in]

Specifies the I/O address within the address space.

Buffer [out]

Receives the data read from the I/O bus.

BufferSize [in]

Specifies the size in bytes of the buffer Buffer. This is the maximum number of bytes that will be read. At present, this must be 1, 2, or 4.

BytesRead [out, optional]

Receives the number of bytes returned read from the I/O bus. If BytesRead is NULL, this information is not returned.

Return value

Return codeDescription

The method was successful.


This method can also return error values. See Return Values for more details.


This method is only available in kernel-mode debugging.



Dbgeng.h (include Dbgeng.h)



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