Type Alias CallbackRestype

Create a callback that can be passed to native functions.

The callback runs on the main thread. For thread-safe callbacks, use threadSafeCallback.

Important: Call .release() when the callback is no longer needed.

Python equivalent: ctypes.CFUNCTYPE(...)(func)

Param: fn

JavaScript function to wrap

Param: returnType

Return type of the callback

Param: argTypes

Argument types

Returns

A wrapper with a .pointer property and .release() method

Example

import { callback, c_int32, c_void_p, readValue } from 'node-ctypes';

const compare = callback(
    (a, b) => readValue(a, c_int32) - readValue(b, c_int32),
    c_int32, [c_void_p, c_void_p]
);
// Pass compare.pointer to qsort, etc.
compare.release();