lc_bcb_68.txt

c++ builder 的一些txt文档

读磁片磁区
读磁片磁区 
一、以前的DOS版要读、写、格式化第0轨的第1个磁区，程式大致如下： 
char buffer[512]; 
reg.x.dx=0 ; /* for drive A * 
reg.x.cx=0x0001 /* for 
boot sector */ 
reg.x.bx=FP_OFF(buffer); 
sreg.es=FP_SEG(buffer); 
resg.x.ax=0x0201; /* 02 for Read, 03 for Write ,05 for 
Format */ 
int86x(0x13,&reg,&reg,&sreg); 
 那麽在windows 下转换为呼叫 DeviceIoControl 
以便格式化、读取、写入该磁轨，DIOC_REGISTERS 这struct 在套上 DOS 下 Int21对HDD或FDD 
的各项参数如要格式化是Int21也是有, 但Windows下也另有提供。 
l#pragma pack(push, 1) 
struct DIOC_REGISTERS { 
 
DWORD reg_EBX; 
 DWORD reg_EDX; 
 
DWORD reg_ECX; 
 DWORD reg_EAX; 
 
DWORD reg_EDI; 
 DWORD reg_ESI; 
 
DWORD reg_Flags; 
}; 
#pragma pack(pop) 
sDiskImageInfo->hDevice = ::CreateFile("\\\\.\\vwin32", 0, 0, NULL, 
0, 
FILE_FLAG_DELETE_ON_CLOSE, NULL); 
if( 
sDiskImageInfo->hDevice == INVALID_HANDLE_VALUE) 
 bRunNext = false; 
// Reset Floppy Disk 
 reg.reg_EBX = 0; 
 reg.reg_EAX = 
0x0000; // IOCTL for block devices 
 reg.reg_EDX = sDiskImageInfo->Driver; 
 reg.reg_EDI = 0; 
reg.reg_ESI= 0; 
 reg.reg_Flags = 0x0001; // 
assume error (carry flag is set) 
 dwResult = ::DeviceIoControl( 
sDiskImageInfo->hDevice, 
VWIN32_DIOC_DOS_INT13, 
 
&reg, sizeof(DIOC_REGISTERS), &reg, 
sizeof(DIOC_REGISTERS), &cb, 
0); 
// Seek Floppy 
 reg.reg_EBX = 0; 
 reg.reg_EAX = 
0x0C00; // IOCTL for block devices 
 reg.reg_ECX = ( sDiskImageInfo->nC 
<< 8) | sDiskImageInfo->nS; 
 
reg.reg_EDX = ( sDiskImageInfo->nH << 8) | sDiskImageInfo->Driver; 
 reg.reg_EDI = 0; 
reg.reg_ESI= 0; 
 reg.reg_Flags = 
0x0001; // assume error (carry flag is set) 
 dwResult = ::DeviceIoControl( 
sDiskImageInfo->hDevice, 
VWIN32_DIOC_DOS_INT13, 
 
&reg, sizeof(DIOC_REGISTERS), &reg, 
sizeof(DIOC_REGISTERS), &cb, 
0); 
// Read Floppy 
R_CreateDiskImageFile: 
 
reg.reg_EBX = 0; 
 reg.reg_EAX = 0x0200 | 
0x01; // IOCTL for block devices 
 reg.reg_ECX = ( sDiskImageInfo->nC 
<< 8) | sDiskImageInfo->nS; 
 
reg.reg_EDX = ( sDiskImageInfo->nH << 8) | sDiskImageInfo->Driver; 
 reg.reg_EBX = (DWORD) &m_Buf; 
 reg.reg_EDI = 0; 
reg.reg_ESI= 0; 
 reg.reg_Flags = 
0x0001; // assume error (carry flag is set) 
 dwResult = ::DeviceIoControl( hDevice, 
VWIN32_DIOC_DOS_INT13, 
 
&reg, sizeof(DIOC_REGISTERS), &reg, 
sizeof(DIOC_REGISTERS), &cb, 
0); 
 if (!dwResult || (reg.reg_Flags & 
0x0001)) 
 { 
}