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| SetFilePointer The SetFilePointer function moves the file pointer of an open file. VB4-32,5,6
Declare Function SetFilePointer Lib "kernel32" Alias "SetFilePointer" (ByVal hFile As Long, ByVal lDistanceToMove As Long, lpDistanceToMoveHigh As Long, ByVal dwMoveMethod As Long) As Long |
VB.NET
System.IO.FileStream.Seek |
| Operating Systems Supported |
| Requires Windows NT 3.1 or later; Requires Windows 95 or later |
· hFile
Identifies the file whose file pointer is to be moved. The file handle must have been created with GENERIC_READ or GENERIC_WRITE access to the file.
· lDistanceToMove
Specifies the number of bytes to move the file pointer. A positive value moves the pointer forward in the file and a negative value moves it backward.
· lpDistanceToMoveHigh
Points to the high-order word of the 64-bit distance to move. If the value of this parameter is NULL, SetFilePointer can operate only on files whose maximum size is 2^32 - 2. If this parameter is specified, the maximum file size is 2^64 - 2. This parameter also receives the high-order word of the new value of the file pointer.
· dwMoveMethod
Specifies the starting point for the file pointer move. This parameter can be one of the following values:
FILE_BEGIN
The starting point is zero or the beginning of the file. If FILE_BEGIN is specified, DistanceToMove is interpreted as an unsigned location for the new file pointer.
FILE_CURRENT
The current value of the file pointer is the starting point.
FILE_END
The current end-of-file position is the starting point. |
If the SetFilePointer function succeeds, the return value is the low-order doubleword of the new file pointer, and if lpDistanceToMoveHigh is not NULL, the function puts the high-order doubleword of the new file pointer into the LONG pointed to by that parameter.
If the function fails and lpDistanceToMoveHigh is NULL, the return value is 0xFFFFFFFF. To get extended error information, call GetLastError.
If the function fails, and lpDistanceToMoveHigh is non-NULL, the return value is 0xFFFFFFFF and GetLastError will return a value other than NO_ERROR. |
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