TWAIN_CAPABILITY structure (wiatwcmp.h)

The TWAIN_CAPABILITY structure holds information used when a TWAIN-compatible application communicates with a WIA driver.

Syntax

typedef struct _TWAIN_CAPABILITY {
  LONG lSize;
  LONG lMSG;
  LONG lCapID;
  LONG lConType;
  LONG lRC;
  LONG lCC;
  LONG lDataSize;
  BYTE Data[1];
} TWAIN_CAPABILITY, *PTWAIN_CAPABILITY;

Members

lSize

Specifies the size, in bytes, of the TWAIN_CAPABILITY structure.

lMSG

Specifies the particular TWAIN message, which can be one of the following values:

Value	Meaning
MSG_GET	Get a capability.
MSG_GETCURRENT	Get the current capability.
MSG_GETDEFAULT	Get the default capability.
MSG_RESET	Reset the capability.
MSG_SET	Set a capability.

lCapID

Specifies the ID of the capability to set or get.

lConType

Specifies the capability's container type.

lRC

Specifies the TWAIN return code. This value can be on of the following:

Value	Meaning
TWRC_FAILURE	The capability specified by the lCapID member is not supported.
TWRC_SUCCESS	The capability specified by the lCapID member is supported.
TWRC_SUCCESS	See the Remarks section.

lCC

Specifies the TWAIN condition code. This value can be one of the following:

Value	Meaning
TWCC_BUMMER	The operation failed for an unknown reason.
TWCC_SUCCESS	The operation was successful.
TWCC_XXX	See the Remarks section.

lDataSize

Specifies the size, in bytes of the data in the Data array.

Data[1]

Is an array that contains the capability data. The actual size, in bytes, of the array is indicated by the lDataSize member.

Remarks

A TWAIN-capable application communicates with a WIA driver by way of the TWAIN compatibility later to find out whether the driver has any private capabilities, and if so, what they are. A TWAIN_CAPABILITY structure is used in this communication. For more information, see TWAIN Compatibility.

The TWAIN return codes and control codes are defined in twain.h, which can be obtained from the TWAIN Working Group.

Requirements

Requirement	Value
Header	wiatwcmp.h (include Wiatwcmp.h)