src/crypto/rand/rand_darwin.go

// Copyright 2024 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package rand

import "internal/syscall/unix"

func init() {
	// arc4random_buf is the recommended application CSPRNG, accepts buffers of
	// any size, and never returns an error.
	//
	// "The subsystem is re-seeded from the kernel random number subsystem on a
	// regular basis, and also upon fork(2)." - arc4random(3)
	//
	// Note that despite its legacy name, it uses a secure CSPRNG (not RC4) in
	// all supported macOS versions.
	altGetRandom = func(b []byte) error { unix.ARC4Random(b); return nil }
}