The BackupSeek function seeks forward in a data stream initially accessed by using the BackupRead or BackupWrite function.
BOOL BackupSeek(
| HANDLE hFile, | // handle to open file |
| DWORD dwLowBytesToSeek, | // low-order 32 bits of number of bytes |
| DWORD dwHighBytesToSeek, | // high-order 32 bits of number of bytes |
| LPDWORD lpdwLowByteSeeked, | // pointer to number of bytes function seeks |
| LPDWORD lpdwHighByteSeeked, | // pointer to number of bytes function seeks |
| LPVOID *lpContext | //pointer to internal context information |
| ); |
Parameters
hFile
Identifies the file or directory being backed up. This handle is created by using the CreateFile function.
dwLowBytesToSeek
Specifies the low-order 32 bits of the number of bytes to seek.
dwHighBytesToSeek
Specifies the high-order 32 bits of the number of bytes to seek.
lpdwLowByteSeeked
Pointer to a doubleword that, when the function returns, contains the low-order 32 bits of the number of bytes the function actually seeks.
lpdwHighByteSeeked
Pointer to a doubleword that, when the function returns, contains the high-order 32 bits of the number of bytes the function actually seeks.
lpContext
Pointer to an internal data structure used by the function. This structure must be the same structure that was initialized by the BackupRead function. An application must not touch the contents of this structure.
Return Values
If the function could seek the requested amount, the function returns nonzero.
If the function could not seek the requested amount, the function returns zero.
Remarks
Applications use the BackUpSeek function to skip portions of a data stream that cause errors. This function does not seek across stream headers. If an application attempts to seek past the end of a substream, the function fails, the lpdwLowByteSeeked and lpdwHighByteSeeked parameters indicate the actual number of bytes the function seeks, and the file position is placed at the start of the next stream header.
See Also