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PFN_CSP_CACHE_LOOKUP_FILE function pointer

This topic is not current. For the most current information about the Smart Card API, see Smart Card Minidriver Specification.

The PFN_CSP_CACHE_LOOKUP_FILE function pointer points to a function that reads a file that was cached by the Microsoft Base Smart Card Cryptographic Service Provider as the result of a previous call that used the PFN_CSP_CACHE_ADD_FILE function pointer.

Syntax

typedef DWORD ( WINAPI *PFN_CSP_CACHE_LOOKUP_FILE)(
  _In_  PVOID  pvCacheContext,
  _In_  LPWSTR wszTag,
  _In_  DWORD  dwFlags,
  _Out_ PBYTE  *ppbData,
  _Out_ PDWORD pcbData
);

Parameters

pvCacheContext [in]

A context value supplied by the Microsoft Base Smart Card Cryptographic Service Provider. This value must be set to the value of the pvCacheContext member of the corresponding CARD_DATA structure.

wszTag [in]

A pointer to a null-terminated wide character string that contains the name of the cached file to read. This name was supplied when the file was cached by using the PFN_CSP_CACHE_ADD_FILE function pointer.

dwFlags [in]

Reserved. This parameter must be set to zero.

ppbData [out]

A pointer to a buffer that receives the data from the cached file.

When memory for this buffer is no longer required, the smart card module must free it by using the PFN_CSP_FREE function pointer.

pcbData [out]

A pointer to a DWORD that receives the size, in bytes, of the data contained in the ppbData buffer.

Return value

If the function succeeds, the function returns zero.

If the function fails, it returns a nonzero value.

Remarks

This function pointer is passed to a card module in a CARD_DATA structure when the Microsoft Base Smart Card Cryptographic Service Provider calls the CardAcquireContext function.

To improve performance by avoiding redundant read/write activity to the card, files on the card that are used only internally by the smart card module can take advantage of caching provided by the Microsoft Base Smart Card Cryptographic Service Provider. This function is used to find a file in the cache.

Requirements

Minimum supported client
Windows XP [desktop apps only]
Minimum supported server
Windows Server 2003 [desktop apps only]
Header
Cardmod.h

See also

CARD_DATA

CardAcquireContext

PFN_CSP_CACHE_ADD_FILE

PFN_CSP_FREE