misc/sys/file.h

   1 /* Copyright (C) 1991, 1992, 1996, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #ifndef _SYS_FILE_H
  20 #define _SYS_FILE_H     1
  21
  22 #include <features.h>
  23
  24 #ifndef _FCNTL_H
  25 # include <fcntl.h>
  26 #endif
  27
  28 __BEGIN_DECLS
  29
  30
  31 /* Alternate names for values for the WHENCE argument to `lseek'.
  32    These are the same as SEEK_SET, SEEK_CUR, and SEEK_END, respectively.  */
  33 #ifndef L_SET
  34 # define L_SET  0       /* Seek from beginning of file.  */
  35 # define L_INCR 1       /* Seek from current position.  */
  36 # define L_XTND 2       /* Seek from end of file.  */
  37 #endif
  38
  39
  40 /* Operations for the `flock' call.  */
  41 #define LOCK_SH 1       /* Shared lock.  */
  42 #define LOCK_EX 2       /* Exclusive lock.  */
  43 #define LOCK_UN 8       /* Unlock.  */
  44
  45 /* Can be OR'd in to one of the above.  */
  46 #define LOCK_NB 4       /* Don't block when locking.  */
  47
  48
  49 /* Apply or remove an advisory lock, according to OPERATION,
  50    on the file FD refers to.  */
  51 extern int __flock __P ((int __fd, int __operation));
  52 extern int flock __P ((int __fd, int __operation));
  53
  54
  55 __END_DECLS
  56
  57 #endif /* sys/file.h  */