L_TwainEnableDuplex

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainEnableDuplex(hSession, bEnableDuplex)

Enables or disables the duplex mode.

Parameters

HTWAINSESSION hSession

Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession or L_TwainInitSession2 function.

L_BOOL bEnableDuplex

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

Value Meaning
TRUE Enable the duplex mode.
FALSE Disable the duplex mode.

Returns

Value Meaning
SUCCESS The function was successful.
< 1 An error occurred. Refer to Return Codes.

Comments

L_TwainEnableDuplex internally sets the duplex-enabled capability CAP_DUPLEXENABLED. For more information on these capabilities, refer to the TWAIN specification.

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

See Also

Functions

Topics

Example

L_INT TwainEnableDuplexExample(HTWAINSESSION hSession) 
{ 
   L_INT nRet; 
   L_BOOL bEnableDuplex; 
   L_INT nDuplexMode; 
 
   nRet = L_TwainStartCapsNeg(hSession); 
   if(nRet != SUCCESS) 
      return nRet;  
 
   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; 
} 
Help Version 21.0.2021.4.7
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2021 LEAD Technologies, Inc. All Rights Reserved.

LEADTOOLS TWAIN C API Help