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─────C/C++ Language─────────────────────────────────────────────────────────
 
  Keyword:  __saveregs
 
  Syntax:   __saveregs declarator
 
  Summary:  Saves and restores CPU registers when entering and exiting
            a function, respectively.
 
  See also:  __loadds, __interrupt, __export
 
     The __saveregs keyword is useful in any case in which it is not
     certain what the register conventions of the caller might be. For
     instance, __saveregs could be used for a general-purpose function
     that will reside in a dynamic-link library. Because a function in
     a dynamic-link library might be called from any language, you may
     choose not to assume Microsoft C calling conventions in some
     cases.
 
     The __saveregs keyword causes the compiler to generate code that
     saves and restores all CPU registers when entering and exiting the
     specified function. Note that __saveregs does not restore registers
     used for a return value (the AX register, or AX and DX).
 
     It is not possible to declare a function with both the __saveregs
     and the __interrupt attributes.
 
     The following statement declares <funcptr> as a far pointer to a
     function with no arguments, returning a char pointer. The presence
     of __saveregs tells the compiler that the function called through
     <funcptr> saves and restores register contents. In this example,
     the __loadds keyword also tells the compiler that the target
     function loads its own data segment.
 
          char *(__far __saveregs __loadds *funcptr)( void );
                                    -♦-