// Copyright 2021 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.

//go:build dragonfly || freebsd || linux || netbsd || openbsd
// +build dragonfly freebsd linux netbsd openbsd

package net

import (
	"internal/syscall/unix"
	"syscall"
)

func fcntl(fd int, cmd int, arg int) (int, error) {
	r, _, e := syscall.Syscall(unix.FcntlSyscall, uintptr(fd), uintptr(cmd), uintptr(arg))
	if e != 0 {
		return int(r), syscall.Errno(e)
	}
	return int(r), nil
}