_TWAIN_CAPABILITY structure

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.
Other TWRC_XXX return code 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

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 (http://www.twain.org).

Requirements

   
Windows version Available in Windows Me and in Windows XP and later versions of the Windows operating systems.
Header wiatwcmp.h (include Wiatwcmp.h)