此函数wincc6.0下不支持的哦！！！
你用它来干什么啊？？？

TLGGetBackupSize
Declaration

BOOL TLGGetBackupSize (
LPTSTR pszArchivName,
DWORD* pdwSizeOfTable,
PTLG_IO_BACKUP_SELECT lpibs,
DWORD dwJobFlags,
DWORD dwFormatFlags,
PCMN_ERROR pError );
Des cription
This function determines the size of data records to be exported.
The function is not available in multi-client projects created with Version V5.0 of WinCC.
In WinCC Version V6.0 or higher, this function is no longer supported. It returns FALSE as the return value and the TLG_API_NOT_SUPPORTED error code.
Parameters
lpszArchivName
Pointer to the name of the archive.
lpdwSizeOfTable
Address of a DWORD to which the size (in bytes) of the selected data is written.
lpibs
Address of the TLG_IO_BACKUP_SELECT structure which passes the selection parameters.
dwJobFlags
Job-specific identification; possible options:
TLG_BACKUP_EXPORT: Simple backup without deleting the source data.
TLG_BACKUP_EVACUATE: Export and delete the sources
dwFormatFlags
Format specifier:
TLG_BAKFMT_CSV: CSV format (Comma Seperated Value)
lpError
Pointer to the data of the extended error message within the CMN_ERROR structure. In the event of an error, the system writes error information to this structure.
Return Value
TRUE
Size of the data has been determined
FALSE
Error
Error Messages
TLG_API_ERR_SUPPLY An error has occurred.
TLG_API_INVALID_PARAM Invalid/incorrect parameter assignment
TLG_API_NO_INTERFACE Access to subordinate COM interfaces failed
TLG_API_NO_CONNECTION A connection to an activated project has not been established
TLG_API_NOT_SUPPORTED This function is not supported
Required Files
pdertcli.h
pde_glob.h
pdertdef.h
pdertcli.lib
pdertcli.dll