1/* Copyright (C) 1991, 92, 96, 97, 98, 99 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 Lesser General Public
6   License as published by the Free Software Foundation; either
7   version 2.1 of the 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   Lesser General Public License for more details.
13
14   You should have received a copy of the GNU Lesser General Public
15   License along with the GNU C Library; if not, write to the Free
16   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17   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.  */
51extern int flock (int __fd, int __operation) __THROW;
52
53
54__END_DECLS
55
56#endif /* sys/file.h  */
57