package main

import (
	"os"

	"golang.org/x/sys/unix"
)

// dupTo makes file descriptor fd refer to f (dup2; linux/arm64 only has
// dup3).
func dupTo(f *os.File, fd int) error {
	if int(f.Fd()) == fd {
		return nil // dup3 fails for the same descriptor
	}
	return unix.Dup3(int(f.Fd()), fd, 0)
}