File 读取FAT16文件系统
我试图阅读FAT16文件系统,以获得有关它的信息,如扇区数、集群数、字节数等 我试着这样读:File 读取FAT16文件系统,file,type-conversion,byte,fat16,File,Type Conversion,Byte,Fat16,我试图阅读FAT16文件系统,以获得有关它的信息,如扇区数、集群数、字节数等 我试着这样读: FILE *floppy; unsigned char bootDisk[512]; floppy = fopen(name, "r"); fread(bootDisk, 1, 512, floppy); int i; for (i = 0; i < 80; i++){ printf("%u,",bootDisk[i]); } 这些数字代表什么?它们是什么类型的?字节?您没有正确读
FILE *floppy;
unsigned char bootDisk[512];
floppy = fopen(name, "r");
fread(bootDisk, 1, 512, floppy);
int i;
for (i = 0; i < 80; i++){
printf("%u,",bootDisk[i]);
}
这些数字代表什么?它们是什么类型的?字节?您没有正确读取值。其中大多数长度超过1字节 从中,您可以获得引导扇区中每个属性的长度和含义:
Offset Size (bytes) Description
0000h 3 Code to jump to the bootstrap code.
0003h 8 Oem ID - Name of the formatting OS
000Bh 2 Bytes per Sector
000Dh 1 Sectors per Cluster - Usual there is 512 bytes per sector.
000Eh 2 Reserved sectors from the start of the volume.
0010h 1 Number of FAT copies - Usual 2 copies are used to prevent data loss.
0011h 2 Number of possible root entries - 512 entries are recommended.
0013h 2 Small number of sectors - Used when volume size is less than 32 Mb.
0015h 1 Media Descriptor
0016h 2 Sectors per FAT
0018h 2 Sectors per Track
001Ah 2 Number of Heads
001Ch 4 Hidden Sectors
0020h 4 Large number of sectors - Used when volume size is greater than 32 Mb.
0024h 1 Drive Number - Used by some bootstrap code, fx. MS-DOS.
0025h 1 Reserved - Is used by Windows NT to decide if it shall check disk integrity.
0026h 1 Extended Boot Signature - Indicates that the next three fields are available.
0027h 4 Volume Serial Number
002Bh 11 Volume Label - Should be the same as in the root directory.
0036h 8 File System Type - The string should be 'FAT16 '
003Eh 448 Bootstrap code - May schrink in the future.
01FEh 2 Boot sector signature - This is the AA55h signature
您可能应该使用自定义结构来读取引导扇区
比如:
请记住实现中的尾数和填充规则。此结构只是一个示例
如果你需要更多的细节,这是一个彻底的例子
Offset Size (bytes) Description
0000h 3 Code to jump to the bootstrap code.
0003h 8 Oem ID - Name of the formatting OS
000Bh 2 Bytes per Sector
000Dh 1 Sectors per Cluster - Usual there is 512 bytes per sector.
000Eh 2 Reserved sectors from the start of the volume.
0010h 1 Number of FAT copies - Usual 2 copies are used to prevent data loss.
0011h 2 Number of possible root entries - 512 entries are recommended.
0013h 2 Small number of sectors - Used when volume size is less than 32 Mb.
0015h 1 Media Descriptor
0016h 2 Sectors per FAT
0018h 2 Sectors per Track
001Ah 2 Number of Heads
001Ch 4 Hidden Sectors
0020h 4 Large number of sectors - Used when volume size is greater than 32 Mb.
0024h 1 Drive Number - Used by some bootstrap code, fx. MS-DOS.
0025h 1 Reserved - Is used by Windows NT to decide if it shall check disk integrity.
0026h 1 Extended Boot Signature - Indicates that the next three fields are available.
0027h 4 Volume Serial Number
002Bh 11 Volume Label - Should be the same as in the root directory.
0036h 8 File System Type - The string should be 'FAT16 '
003Eh 448 Bootstrap code - May schrink in the future.
01FEh 2 Boot sector signature - This is the AA55h signature
typedef struct {
unsigned char jmp[3];
char oem[8];
unsigned short sector_size;
unsigned char sectors_per_cluster;
unsigned short reserved_sectors;
unsigned char number_of_fats;
unsigned short root_dir_entries;
[...]
} my_boot_sector;