Define a union (FFI for Emacs)

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2.8 Define a union ¶

(define-ffi-union NAME &rest SLOT...). Like define-ffi-struct, but defines a union.

(define-ffi-union test-union
  (cval :type :uchar)
  (ival :type :int))

(define-ffi-function test-get-union "test_get_union"
  test-union nil test.so)

(let ((object (test-get-union)))
    (list (test-union-ival object)
          (test-union-cval object))) ; => (-1 25)