The Art of SQL Server FILESTREAM - Red Gate Software

Chapter 3: Accessing FILESTREAM Data from Client ApplicationsThe default location is C:\Program Files\Microsoft SQL Server\100\SDK\Include, but you might find it in a different location, depending upon where youinstalled SQL Server 2008.The code snippet in Listing 3-36 shows an example that opens a FILESTREAM data fileusing the OpenSqlFilestream API function.//Get a handle to the FILESTREAM data using OpenSqlFileStream APIHANDLE srcHandle = INVALID_HANDLE_VALUE;srcHandle = OpenSqlFilestream ( dstFilePath, SQL_FILESTREAM_READ, 0,transactionToken,cbTransactionToken, 0);Listing 3-36:Opening a FILESTREAM data file for READ access with C++ using Win32 APIOpenSqlFileStream().The first argument (dstFilePath) is the logical path to the FILESTREAM data file,retrieved by a call to the PathName() function on the FILESTREAM column. The secondargument specifies the file access level required. This argument can take one of the valueslisted below.• SQL_FILESTREAM_READ – Opens the FILESTREAM data file for reading. The filepointer is placed at the beginning of the file.• SQL_FILESTREAM_WRITE – Opens the FILESTREAM data file for writing. The filepointer is placed at the beginning of the file. A write operation will overwrite theexisting content in the file.• SQL_FILESTREAM_READWRITE – Opens the FILESTREAM data file for reading andwriting. The file pointer is placed at the beginning of the file. You can use the Seek()method to move the file pointer to specific locations in the file and make partialupdates, or to move to the end of the file to append content.127