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─────C/C++ Language─────────────────────────────────────────────────────────
 
  Keyword:   __export
 
  Syntax:    __export declarator
 
  Summary:   Specifies that a symbol is exported from a dynamic-link
             library (DLL). Any of the following can be declared as
             __export:
 
                ■ Data
 
                ■ Functions
 
                ■ Member functions
 
                ■ Constructors
 
                ■ Destructors
 
                ■ Operators
 
  See also:  LINK, IMPLIB
            ◄EXPORTS Statement►
            ◄Module-Definition Files►
 
     The main use for __export is to export symbols that reside in a
     dynamic-link library. You can also need to export call-back
     functions for Microsoft Windows or for PWB extensions.
 
     When you use the __export keyword, the linker assumes the exported
     symbol has the following attributes:
 
        ■ No input/output (I/O) privileges
 
        ■ Shared data
 
        ■ Not resident
 
        ■ No alias name
 
     If you want to alter these attributes, you must use a
     module-definition (.DEF) file with an EXPORTS statement when
     building a DLL.
     See: ◄EXPORTS Statement►
 
     The __export keyword also causes the compiler to enter the size,
     in words, of the function's parameters into the export record of
     the object module. This size information corresponds to the
     <pwords> field of an EXPORTS statement that is in a .DEF file. You
     cannot override the size information in the export record with an
     EXPORTS entry in the .DEF file.
 
     If you have an EXPORTS entry for a function, the <pwords> field in
     the .DEF file should be set either to 0 (which tells the linker to
     use the value given by the compiler) or to the same value given
     by the compiler. The <pwords> field is ignored unless you also
     request I/O privilege.
 
     You can create an import library for a DLL in the following
     manner:
 
        1. Provide a .DEF file entry for every symbol that you want to
           export.
 
        2. Use the IMPLIB utility. It creates a file with a .LIB
           extension for use by the linker. Specify the .LIB file on
           the LINK line with the other libraries.
 
     See: ◄IMPLIB Summary►
 
     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 );
                                    -♦-