// 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 && mips64) 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 }