golang dup3 代码
文件路径：/misc/cgo/testcshared/testdata/libgo2/dup3.go
/ Copyright 2015 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.
/ +build linux,arm64 linux,riscv64
package main
import "syscall"
func dup2(oldfd, newfd int) error {
return syscall.Dup3(oldfd, newfd, 0)
}