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4/8/2010

This function gives you direct control of the reader. You can call it any time after a successful call to SCardConnectand before a successful call to SCardDisconnect. The effect on the state of the reader depends on the control code.

Syntax 

LONG SCardControl(
  SCARDHANDLE 
hCard, 
  DWORD 
dwControlCode, 
  LPCVOID 
lpInBuffer, 
  DWORD 
nInBufferSize, 
  LPVOID 
lpOutBuffer, 
  DWORD 
nOutBufferSize, 
  LPDWORD 
lpBytesReturned 
);

Parameters

hCard

[in] Handle to a reference value returned from SCardConnect.

dwControlCode

[in] Specifies the control code for the operation. This value identifies the specific operation to be performed.

lpInBuffer

[in] Long pointer to a buffer that contains the data required to perform the operation. This parameter can be NULL if the dwControlCodeparameter specifies an operation that does not require input data.

nInBufferSize

[in] Integer that specifies the size, in bytes, of the buffer pointed to by lpInBuffer.

lpOutBuffer

[out] Long pointer to a buffer that receives the operation's output data. This parameter can be NULL if the dwControlCodeparameter specifies an operation that does not produce output data.

nOutBufferSize

[in] Integer that specifies the size, in bytes, of the buffer pointed to by lpOutBuffer.

lpBytesReturned

[out] Long pointer to a DWORDthat receives the size, in bytes, of the data stored into the buffer pointed to by lpOutBuffer.

Return Value

The following table shows the possible return values.

Value Description

SCARD_S_SUCCESS

Succeeds

An error value (see Smart Card Error Valuesfor a list of all error values).

Fails

Remarks

SCardControlis a direct card access function.

Requirements

Header winscard.h
Library winscard.lib
Windows Embedded CE Windows CE 3.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also