Backward Compatibility

Visual Studio 6.0

The compiler views a structure that has both an old name and a new name as two different types. You cannot copy from an old structure type to a new structure type. Old prototypes that take struct pointers use the old struct names in the prototype.

For compatibility with Microsoft C professional development system version 6.0 and earlier Microsoft C versions, the library OLDNAMES.LIB maps old names to new names. For instance, open maps to _open. You must explicitly link with OLDNAMES.LIB only when you compile with the following combinations of command-line options:

  • /Zl (omit default library name from object file) and /Ze (the default — use Microsoft extensions)

  • /link (linker-control), /NOD (no default-library search), and /Ze

For more information about compiler command-line options, see Compiler Reference in the Visual C++ Programmer’s Guide.