LTwain::LockContainer

#include "ltwrappr.h"

virtual L_INT LTwain::LockContainer(pCapability, ppContainer)

TW_CAPABILITY * pCapability;	/* pointer to a structure */
void ** ppContainer;	/* pointer to a pointer to a structure */

Gets the container information for the specified capability.

Parameter	Description
pCapability	Pointer to a TW_CAPABILITY structure from which to get the container.
ppContainer	Pointer to be updated with a pointer to the container.

Returns

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

Comments

This function is used to lock the container present in the TW_CAPABILITY structure.

Once the user has the pointer to the container, the container may be changed. When the user has finished changing the container he or she must call LTwain::UnlockContainer to unlock the container. Note that this can also be accomplished using the C DLL GlobalLock and GlobalUnlock functions.

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:	LTwain::UnlockContainer.
Topics:	How to Work with the Containers
	TWAIN Functionality: Container Functions.

Example

L_INT LTwain__LockContainerExample(LTwain *MyClass)
{
   L_INT          nRet;
   TW_CAPABILITY  twCap;
   TW_ONEVALUE *  ptwOneVal = NULL; 
   twCap.Cap = ICAP_XFERMECH; 
   twCap.ConType = TWON_DONTCARE16; 
   nRet = MyClass->GetCapability(&twCap, LTWAIN_CAPABILITY_GETCURRENT); 
   if (nRet != SUCCESS) 
   {
      MessageBox (NULL, TEXT("Failed to get capability"), TEXT("ERROR"), MB_OK); 
      return nRet; 
   }
   if (twCap.ConType == TWON_ONEVALUE)
   {
      nRet = MyClass->LockContainer(&twCap, (void **)&ptwOneVal); 
      if(nRet != SUCCESS)
         return nRet;
      if (ptwOneVal) 
      {
         // Do processing
         nRet = MyClass->UnlockContainer(&twCap); 
         if(nRet != SUCCESS)
            return nRet;
      }
   }
   return SUCCESS;
}