L_Doc2SetProgressCB
#include "ltdoc2.h"
L_LTDOC2_API L_INT EXT_FUNCTION L_Doc2SetProgressCB(hDoc, pfnCallback, pUserData)
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 L_HDOC2 hDoc;  | 
 /* handle to the OCR document */  | 
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 PROGRESSCALLBACK2 pfnCallback;  | 
 /* callback function */  | 
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 L_VOID * pUserData;  | 
 /* pointer to more parameters for the callback */  | 
Sets the progress callback function that should be used by the OCR engine to report progress and offer the client the opportunity to cancel.
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 Parameter  | 
 Description  | 
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 hDoc  | 
 Handle to the OCR document.  | 
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 pfnCallback  | 
 Optional callback function for reporting progress of a specific operation.  | 
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 If you do not provide a callback function, use NULL as the value of this parameter. Use NULL if no progress reporting is needed. If you do provide a callback function, use the function pointer as the value of this parameter.  | 
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 The OCR engine calls this callback function as it reports the progress of a specific operation.  | 
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 The callback function must adhere to the following function prototype: PROGRESSCALLBACK2.  | 
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 pUserData  | 
 Void pointer that you can use to pass one or more additional parameters that the callback function needs.  | 
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 To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID *. The callback function, which receives the address in its own pUserData parameter, can cast it to a pointer to the appropriate data type to access your variable or structure.  | 
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 If the additional parameters are not needed, you can pass NULL in this parameter.  | 
Returns
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 SUCCESS  | 
 The function was successful.  | 
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 < 1  | 
 An error occurred. Refer to Return Codes.  | 
Comments
To get the current process, check the Id member of the PROGRESSDATA2 structure, which is passed to the PROGRESSCALLBACK2 function.
Refer to the DOC2_OCRPROCID enumeration for the event types that can be reported to the progress callback.
Required DLLs and Libraries
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 LTDOC2 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
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 Functions:  | 
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 Topics:  | 
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Example
L_BOOL EXT_CALLBACK DocSetProgressCB(pPROGRESSDATA2 pProgressData, L_VOID* pUserData)
{
   UNREFERENCED_PARAMETER(pUserData);
   if (pProgressData->Id == DOC2_PROC_FIND_ZONES)
      MessageBox(NULL, TEXT("The current process is finding zones in a specific page."), TEXT("Notice!"), MB_OK);
   //...
   //... Your code here
   //...
   return TRUE;
}
L_LTDOC2TEX_API  L_INT Doc2SetProgressCBExample(L_HDOC2 hDoc)
{
   L_INT nRet;
   nRet = L_Doc2SetProgressCB(hDoc, DocSetProgressCB, NULL);
   if(nRet != SUCCESS)
      return nRet;
   return SUCCESS;
}