The ReadBinary method constructs an APDU command that acquires a response message that gives that part of the contents of a transparent-structured elementary file.
HRESULT ReadBinary(
BYTE byP1,
BYTE byP2,
LONG lBytesToRead,
LPSCARDCMD *ppCmd
);
If b8=1 in P1, then b7 and b6 of P1 are set to 0 (RFU bits), b5 to b1 of P1 are a short EF identifier and P2 is the offset of the first byte to be read in data units from the beginning of the file.
If b8=0 in P1, then P1||P2 is the offset of the first byte to be read in data units from the beginning of the file.
If the Le field contains only zeroes, then within the limit of 256 for short length or 65536 for extended length, all the bytes until the end of the file should be read.
On return, it is filled with the APDU command constructed by this operation. If ppCmd was set to NULL, a smart card ISCardCmd object is internally created and returned via the ppCmd pointer.
The possible return values are the following:
| Value | Meaning |
|---|---|
| S_OK | Operation completed successfully. |
| E_INVALIDARG | Invalid parameter. |
| E_POINTER | A bad pointer was passed in. |
| E_OUTOFMEMORY | Out of memory. |
The encapsulated command can only be performed if the security status of the smart card satisfies the security attributes of the elementary file being processed.
When the command contains a valid short elementary identifier, it sets the file as current elementary file.
Elementary files without a transparent structure cannot be erased. The encapsulated command aborts if applied to an elementary file without a transparent structure.
For a list of all the methods provided by the ISCardISO7816 interface, see ISCardISO7816.
In addition to the COM error codes listed above, this interface may return a smart card error code if a smart card function was called to complete the request. For information on smart card error codes, see Error Codes.
Windows NT: Use version 4.0 SP3 and later.
Windows: Use Windows 95 OSR2.1.
Windows CE: Unsupported.
Header: Declared in scardsrv.h.
Import Library: scardsrv.tlb.
EraseBinary, ISCardISO7816, UpdateBinary, WriteBinary