L_TwainEnableDuplex

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainEnableDuplex(hSession, bEnableDuplex)

HTWAINSESSION hSession;

/* handle to an existing TWAIN session */

L_BOOL bEnableDuplex;

/* flag */

Enables or disables the duplex mode.

Parameter

Description

hSession

Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession function.

bEnableDuplex

Flag that indicates whether to enable or disable the duplex mode. Possible values are:

 

Value

Meaning

 

TRUE

Enables the duplex mode.

 

FALSE

Disables the duplex mode.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

This function internally sets the duplex enabled capability CAP_DUPLEXENABLED. For more information on these capabilities, refer to www.twain.org/download.htm and click on the TWAIN Specification (Version 1.9).

To get the current values of these capabilities, call the L_TwainGetDuplexOptions function.

This function should be called after calling the L_TwainStartCapsNeg function and before calling the L_TwainEndCapsNeg function.

Required DLLs and Libraries

LTTWN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

See Also

Functions:

L_TwainSetTransferOptions, L_TwainGetTransferOptions, L_TwainGetSupportedTransferMode, L_TwainSetResolution, L_TwainGetResolution, L_TwainSetImageFrame, L_TwainGetImageFrame, L_TwainSetImageUnit, L_TwainGetImageUnit, L_TwainSetImageBitsPerPixel, L_TwainGetImageBitsPerPixel, L_TwainSetImageEffects, L_TwainGetImageEffects, L_TwainSetAcquirePageOptions, L_TwainGetAcquirePageOptions, L_TwainSetRGBResponse, L_TwainShowProgress, L_TwainGetDuplexOptions, L_TwainSetMaxXferCount, L_TwainGetMaxXferCount

Topics:

Getting and Setting Capabilities

 

TWAIN Functionality: Capability Functions

Example

L_INT TwainEnableDuplexExample(HTWAINSESSION hSession)
{
   L_INT nRet;
   L_TwainStartCapsNeg (hSession);

   L_BOOL bEnableDuplex;
   L_INT nDuplexMode;

   nRet = L_TwainGetDuplexOptions (hSession, &bEnableDuplex, &nDuplexMode);
   if(nRet != SUCCESS)
      return nRet;
   if (bEnableDuplex != TRUE)
   {
      nRet = L_TwainEnableDuplex(hSession, TRUE);
      if(nRet != SUCCESS)
         return nRet;
   }

   L_INT nMaxXfer;
   nRet = L_TwainGetMaxXferCount (hSession, &nMaxXfer);
   if(nRet != SUCCESS)
      return nRet;
   if (nMaxXfer != 10) 
   {
      nRet = L_TwainSetMaxXferCount (hSession, 10);
      if(nRet != SUCCESS)
         return nRet;
   }

   nRet = L_TwainEndCapsNeg (hSession);
   if(nRet != SUCCESS)
      return nRet;
   return SUCCESS;
}