LTwain::QueryFileSystem

Summary

Performs certain tasks, or retrieves certain information, depending on the value of the FileMsg parameter.

Syntax

L_INT LTwain::QueryFileSystem (FileMsg, pTwFile)

Parameters

FILESYSTEMMSG FileMsg

Files system messages that determine the behavior of the function. For possible values, refer to the FILESYSTEMMSG.

pTW_FILESYSTEM pTwFile

Pointer to a TW_FILESYSTEM structure. This structure will be updated with, or will contain information used to change, the current TWAIN file system settings. This structure must be allocated.

Returns

Comments

This function is only valid for TWAIN file systems for digital cameras.

If the FileMsg parameter contains one of the following flags, the pTwFile parameter must contain the proper information before calling this function. The provided information is needed to change settings within the TWAIN file system.

• FILESYSTEMMSG_CHANGEDIRECTORY
• FILESYSTEMMSG_CREATEDIRECTORY
• FILESYSTEMMSG_DELETE
• FILESYSTEMMSG_FORMATMEDIA
• FILESYSTEMMSG_RENAME
• FILESYSTEMMSG_COPY

If the FileMsg parameter contains one of the following flags, this function will update the pTwFile parameter with the corresponding information.

• FILESYSTEMMSG_GETCLOSE
• FILESYSTEMMSG_GETFIRSTFILE
• FILESYSTEMMSG_GETINFO
• FILESYSTEMMSG_GETNEXTFILE

If the FileMsg parameter contains the following flag, this function will use information stored within the pTwFile parameter and will update the pTwFile parameter with any appropriate information.

• FILESYSTEMMSG_AUTOMATICCAPTUREDIRECTORY

For more information on the TW_FILESYSTEM structure, refer to the TWAIN specification.

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::InitSession
• LTwain::EndSession

Topics

• Getting or Setting TWAIN File System Information
• TWAIN Functionality: Twain File System Functions

Example

L_INT LTwain__QueryFileSystemExample(HWND hWnd) 
{ 
   L_INT             nRet; 
   LTwain            TwainSession; 
   APPLICATIONDATA   AppData; 
   TW_FILESYSTEM     twFileSys; 
 
   memset(&AppData, 0, sizeof(APPLICATIONDATA)); 
 
   AppData.hWnd = hWnd;  
 
   AppData.uStructSize = sizeof(AppData); 
 
   lstrcpy (AppData.szManufacturerName, _T("LEAD Technologies, Inc."));  
   lstrcpy (AppData.szAppProductFamily, _T("LEAD Test Applications")); 
   lstrcpy (AppData.szVersionInfo, _T("Version 1.0")); 
   lstrcpy (AppData.szAppName, _T("TWAIN Test Application")); 
 
   nRet = TwainSession.InitSession(&AppData);  
   if (nRet != TWAIN_SUCCESS) 
   { 
      MessageBox(hWnd, TEXT("Error occurred during call InitSession"), TEXT("Notice"), MB_OK); 
      return nRet; 
   } 
 
   memset(&twFileSys, 0, sizeof(TW_FILESYSTEM)); 
 
   nRet = TwainSession.QueryFileSystem(FILESYSTEMMSG_AUTOMATICCAPTUREDIRECTORY, &twFileSys); 
   if (nRet != TWAIN_SUCCESS) 
   { 
      MessageBox(hWnd, TEXT("Error occurred during call QueryFileSystem"), TEXT("Notice"), MB_OK); 
      return nRet; 
   } 
 
   nRet = TwainSession.EndSession(); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   return SUCCESS; 
}