IOCTL_DISK_PERFORMANCE info  Overview  Group

The IOCTL_DISK_PERFORMANCE DeviceIoControl operation provides disk performance information.

dwIoControlCode = IOCTL_DISK_PERFORMANCE;   // operation code 

lpInBuffer = NULL; // address of input buffer; not used; must be NULL 

nInBufferSize = 0; // size of input buffer; not used; must be zero 

lpOutBuffer;       // address of output buffer 

nOutBufferSize;    // size of output buffer 

lpBytesReturned;   // address of actual bytes of output 

 

Parameters

lpInBuffer

Points to an input buffer. Not used with this operation. Set to NULL.

nInBufferSize

Specifies the size, in bytes, of the buffer pointed to by lpInBuffer. Not used with this operation. Set to zero.

lpOutBuffer

Points to a buffer that will receive a DISK_PERFORMANCE data structure.

nOutBufferSize

Specifies the size, in bytes, of the buffer pointed to by lpOutBuffer, which must be large enough to contain a DISK_PERFORMANCE data structure.

lpBytesReturned

Points to a DWORD that receives the actual size, in bytes, of the data stored into lpOutBuffer.

Return Values

If the operation succeeds, DeviceIoControl returns a nonzero value.

If the operation fails, DeviceIoControl returns zero. To get extended error information, call GetLastError.

Remarks

This device I/O control operation is for disk devices.

See Also

DeviceIoControl, DISK_PERFORMANCE