napi create external buffer

napi_status napi_create_external_buffer(napi_env env,
                                        size_t length,
                                        void* data,
                                        napi_finalize finalize_cb,
                                        void* finalize_hint,
                                        napi_value* result)

• [in] env: The environment that the API is invoked under.
• [in] length: Size in bytes of the input buffer (should be the same as the size of the new buffer).
• [in] data: Raw pointer to the underlying buffer to expose to JavaScript.
• [in] finalize_cb: Optional callback to call when the ArrayBuffer is being collected. [napi_finalize][] provides more details.
• [in] finalize_hint: Optional hint to pass to the finalize callback during collection.
• [out] result: A napi_value representing a node::Buffer.

Returns napi_ok if the API succeeded.

This API allocates a node::Buffer object and initializes it with data backed by the passed in buffer. While this is still a fully-supported data structure, in most cases using a TypedArray will suffice.

The API adds a napi_finalize callback which will be called when the JavaScript object just created is ready for garbage collection. It is similar to napi_wrap() except that:

• the native data cannot be retrieved later using napi_unwrap(),
• nor can it be removed later using napi_remove_wrap(), and
• the object created by the API can be used with napi_wrap().

For Node.js >=4 Buffers are Uint8Arrays.