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  Keyword:  _export
 
  Syntax:   _export declarator
 
  Summary:  Exports a function from a dynamic-link library.
 
     When present in a function declaration or definition, the _export
     keyword causes the compiler to place information in the object
     file to show that this function can be exported from a protected-
     mode dynamic-link library.
 
     The main use for _export is to create functions that will reside
     in a dynamic-link library. However, you may also need to export
     functions for Microsoft Windows(TM) or for the Presentation
     Manager.
 
     This feature does not necessarily eliminate the need for a module-
     definition (.DEF) file when building a dynamic-link library. If no
     module-definition entry exists for the function that is to be
     exported, the linker assumes that the function has certain
     characteristics. Namely, it assumes that the function has no
     input/output (I/O) privilege, has shared data, is not resident,
     and has no alias name.
 
     If these default characteristics are satisfactory, as they will be
     in many cases, the function in question does not require an entry
     in a module-definition file. If they are not satisfactory,
     however, you must create an EXPORTS entry for the function. This
     is because the only way to specify these characteristics is in a
     module-definition file.
 
     The _export keyword also causes the compiler to place the number
     of parameter words for the function into the export record in the
     object module. This information corresponds to the iopl_parmwords
     field in an EXPORTS statement in a module-definition file. You
     cannot override this information with an EXPORTS entry in the
     module-definition file.
 
     If you do have an EXPORTS entry for a function, the iopl_parmwords
     field in that entry should be set either to 0 (which tells the
     linker to use the same value given by the compiler), or to the
     same value given by the compiler. Note that the iopl_parmwords
     field is ignored unless you also request I/O privilege.
 
     If you wish to create an import library for the dynamic-link
     library containing the function in question, you must provide a
     module-definition-file entry for every function that you wish to
     export.
 
     The following statement declares funcsample as a far pascal
     function that takes a single argument of any pointer type and does
     not return a value. The presence of _export causes the function to
     be exported.
 
          void _export _far _pascal funcsample( void *s );
                                    -♦-