The DB-Library functions are stored in a dynamic-link library, MSDBLIB3.DLL. Windows Net-Libraries are also implemented as DLLs. For example, DBNMP3.DLL connects to SQL Server over named pipes. Set the PATH environment variable to include the directory in which the libraries reside.
Another file, called MSDBLIB3.LIB, contains the import definitions that your application will use. Set the LIB environment variable to include the directory where MSDBLIB3.LIB resides.