1 /* Provide a more complete sys/file.h.
3 Copyright (C) 2007-2008 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software Foundation,
17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
19 /* Written by Richard W.M. Jones. */
20 #ifndef _GL_SYS_FILE_H
23 @PRAGMA_SYSTEM_HEADER@
26 /* The include_next requires a split double-inclusion guard. */
27 # if @HAVE_SYS_FILE_H@
28 # @INCLUDE_NEXT@ @NEXT_SYS_FILE_H@
31 #ifndef _GL_SYS_FILE_H
32 #define _GL_SYS_FILE_H
36 /* Apply or remove advisory locks on an open file.
37 Return 0 if successful, otherwise -1 and errno set. */
39 extern int flock (int fd, int operation);
41 /* Operations for the 'flock' call (same as Linux kernel constants). */
42 #define LOCK_SH 1 /* Shared lock. */
43 #define LOCK_EX 2 /* Exclusive lock. */
44 #define LOCK_UN 8 /* Unlock. */
46 /* Can be OR'd in to one of the above. */
47 #define LOCK_NB 4 /* Don't block when locking. */
50 #elif defined GNULIB_POSIXCHECK
52 # define flock(fd,op) \
53 (GL_LINK_WARNING ("flock is unportable - " \
54 "use gnulib module flock for portability"), \
59 #endif /* _GL_SYS_FILE_H */
60 #endif /* _GL_SYS_FILE_H */