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─────C/C++ Language─────────────────────────────────────────────────────────
 
  Keyword:   __interrupt
 
  Syntax:    __interrupt <declarator>
 
  Summary:   Specifies that a function is an interrupt handler.
             The compiler generates entry and exit sequences for the
             interrupt handler, including saving and restoring all
             registers and executing an IRET instruction to return.
 
  See also:  _chain_intr, _dos_getvect, _dos_keep, _dos_setvect
 
     The __interrupt keyword is used in C to label a function as an
     interrupt handler. It can also be applied to static member
     functions in C++. An interrupt handler cannot be declared inline.
 
     An interrupt handler must be a far function. If you are compiling
     with the small (default) or compact memory model, you must declare
     your interrupt handler with the __far attribute.
 
     An interrupt handler must use the C calling convention. If you
     use the /Gc or /Gr compiler options, you must declare your
     interrupt handler with the __cdecl attribute.
 
     You cannot declare an interrupt handler with either the __saveregs
     attribute or the _fastcall calling convention.
 
     If the /Zc compiler switch is used, both interrupt and _interrupt
     are synonyms for __interrupt. If /Za is used, only __interrupt
     is accepted.
 
     See: ◄Interrupt Handler Parameters►
          ◄Transferring Interrupt Control►
          ◄Special Considerations►
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