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. */ 51 extern int flock (int __fd, int __operation) __THROW; 52 53 54 __END_DECLS 55 56 #endif /* sys/file.h */ 57