vendor/golang.org/x/sys/unix/fcntl.go

   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
   5 // +build dragonfly freebsd linux netbsd openbsd
   6
   7 package unix
   8
   9 import "unsafe"
  10
  11 // fcntl64Syscall is usually SYS_FCNTL, but is overridden on 32-bit Linux
  12 // systems by flock_linux_32bit.go to be SYS_FCNTL64.
  13 var fcntl64Syscall uintptr = SYS_FCNTL
  14
  15 // FcntlInt performs a fcntl syscall on fd with the provided command and argument.
  16 func FcntlInt(fd uintptr, cmd, arg int) (int, error) {
  17         valptr, _, errno := Syscall(fcntl64Syscall, fd, uintptr(cmd), uintptr(arg))
  18         var err error
  19         if errno != 0 {
  20                 err = errno
  21         }
  22         return int(valptr), err
  23 }
  24
  25 // FcntlFlock performs a fcntl syscall for the F_GETLK, F_SETLK or F_SETLKW command.
  26 func FcntlFlock(fd uintptr, cmd int, lk *Flock_t) error {
  27         _, _, errno := Syscall(fcntl64Syscall, fd, uintptr(cmd), uintptr(unsafe.Pointer(lk)))
  28         if errno == 0 {
  29                 return nil
  30         }
  31         return errno
  32 }