Backward Compatibility
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The latest version of this topic can be found at Backward Compatibility.
For compatibility between product 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.