DVTARGETDEVICE structure (objidl.h)

Specifies information about the target device for which data is being composed. DVTARGETDEVICE contains enough information about a Windows target device so a handle to a device context (HDC) can be created using the CreateDC function.

Syntax

typedef struct tagDVTARGETDEVICE {
  DWORD tdSize;
  WORD  tdDriverNameOffset;
  WORD  tdDeviceNameOffset;
  WORD  tdPortNameOffset;
  WORD  tdExtDevmodeOffset;
  BYTE  tdData[1];
} DVTARGETDEVICE;

Members

tdSize

The size, in bytes, of the DVTARGETDEVICE structure. The initial size is included so the structure can be copied more easily.

tdDriverNameOffset

The offset, in bytes, from the beginning of the structure to the device driver name, which is stored as a NULL-terminated string in the tdData buffer.

tdDeviceNameOffset

The offset, in bytes, from the beginning of the structure to the device name, which is stored as a NULL-terminated string in the tdData buffer. This value can be zero to indicate no device name.

tdPortNameOffset

The offset, in bytes, from the beginning of the structure to the port name, which is stored as a NULL-terminated string in the tdData buffer. This value can be zero to indicate no port name.

tdExtDevmodeOffset

The offset, in bytes, from the beginning of the structure to the DEVMODE structure retrieved by calling DocumentProperties.

tdData[1]

An array of bytes containing data for the target device. It is not necessary to include empty strings in tdData (for names where the offset value is zero).

Remarks

Some OLE 1 client applications incorrectly construct target devices by allocating too few bytes in the DEVMODE structure for the DVTARGETDEVICE. They typically only supply the number of bytes in the dmSize member of DEVMODE. The number of bytes to be allocated should be the sum of dmSize + dmDriverExtra. When a call is made to the CreateDC function with an incorrect target device, the printer driver tries to access the additional bytes and unpredictable results can occur. To help protect against a crash and make the additional bytes available, OLE pads the size of OLE 2 target devices created from OLE 1 target devices.

Requirements

See also

FORMATETC

IEnumFORMATETC

IViewObject

OleConvertOLESTREAMToIStorage