1// Copyright 2014 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package syscall
6
7import "unsafe"
8
9// fcntl64Syscall is usually SYS_FCNTL, but is overridden on 32-bit Linux
10// systems by flock_linux_32bit.go to be SYS_FCNTL64.
11var fcntl64Syscall uintptr = SYS_FCNTL
12
13// FcntlFlock performs a fcntl syscall for the [F_GETLK], [F_SETLK] or [F_SETLKW] command.
14func FcntlFlock(fd uintptr, cmd int, lk *Flock_t) error {
15	_, _, errno := Syscall(fcntl64Syscall, fd, uintptr(cmd), uintptr(unsafe.Pointer(lk)))
16	if errno == 0 {
17		return nil
18	}
19	return errno
20}
21