关于读取独占文件的问题

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各位达人，请问在fat32下和ntfs下读取独占文件的时候，有何不同？因为ntfs的可以读取，但是fat32的始终不行，字节数是正确的，但是内容是错误的,一直找不到原因，恳请各位达人指点.

chenhui530曾经指点过，fat下偏移量需要加上保留扇区+fatarearcount*2 ,不明白这句话是修改什么地方,是不是修改下边的函数呢？

Call SetFilePointer(hDrive, ligNo.LowPart, ligNo.HighPart, 0)

[Yofoo]

FAT32的文件数据区 = 保留扇区 + FAT区 + FDT区

我以前写了类似的代码给你参考:

	#pragma pack(1)
	typedef struct _Fat32BootData
	{
		BYTE jump[3];				//	0x00 Boot strap short or near jump
		char bsOemName[8];			//	0x03 Name - can be used to special case partition manager volumes
		WORD BytesPerSector;		//	0x0B bytes per logical sector
		BYTE SectorsPerCluster;		//	0x0D sectors/cluster
		WORD ReservedSectors;		//	0x0E reserved sectors
		BYTE NumberOfFATs;			//	0x10 number of FATs
		WORD RootEntries;			//	0x11 root directory entries
		WORD TotalSectors;			//	0x13 number of sectors
		BYTE MediaDescriptor;		//	0x15 media code (unused)
		WORD SectorsPerFAT;			//	0x16 sectors/FAT	FAT16
		WORD SectorsPerTrack;		//	0x18 sectors per track
		WORD Heads;					//	0x1A number of heads
		DWORD HiddenSectors;		//	0x1C hidden sectors (unused)
		DWORD BigTotalSectors;		//	0x20 number of sectors (if sectors == 0)
//	The following fields are only used by FAT32
		DWORD BigSectorsPerFat;		//	0x24 sectors/FAT	FAT32
		WORD ExtFlags;				//	0x28 bit 8: fat mirroring, low 4: active fat
		WORD FS_Version;			//	0x2A major, minor filesystem version
		DWORD RootDirStrtClus;		//	0x2C first cluster in root directory
		WORD FSInfoSec;				//	0x30 filesystem info sector
		WORD BkUpBootSec;			//	0x32 backup boot sector
		WORD Reserved[6];			//	0x34 Unused
		BYTE bsDriveNumber;			//	0x40
		BYTE bsReserved;			//	0x41
		BYTE bsBootSignature;		//	0x42
		DWORD bsVolumeID;			//	0x43
		char bsVolumeLabel[11];		//	0x47
		char bsFileSysType[8];		//	0x52
		BYTE unused [422];			//	0x5A
	}Fat32BootData;
#pragma pack()


	DWORD		dwReservedSectors;
	DWORD		dwFatSectors;
	DWORD		dwDirtoryTableSectors;

	dwReservedSectors = Boot.ReservedSectors;
	dwFatSectors = Boot.BigSectorsPerFat * Boot.NumberOfFATs;	//FAT32
	dwDirtoryTableSectors = ((Boot.RootEntries * 32 - 1) / m_dwBytesPerSector + 1) * m_dwBytesPerSector;

	m_dwFat32FirstDataSector = dwReservedSectors + dwFatSectors + dwDirtoryTableSectors;

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谢谢了