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glibc  2.9
fcntl.h
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00001 /* O_*, F_*, FD_* bit values for stub configuration.
00002    Copyright (C) 1991, 1992, 1997, 2000, 2004 Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 /* These values should be changed as appropriate for your system.  */
00021 
00022 #ifndef       _FCNTL_H
00023 # error "Never use <bits/fcntl.h> directly; include <fcntl.h> instead."
00024 #endif
00025 
00026 
00027 /* File access modes for `open' and `fcntl'.  */
00028 #define       O_RDONLY      0      /* Open read-only.  */
00029 #define       O_WRONLY      1      /* Open write-only.  */
00030 #define       O_RDWR        2      /* Open read/write.  */
00031 
00032 
00033 /* Bits OR'd into the second argument to open.  */
00034 #define       O_CREAT              0x0200 /* Create file if it doesn't exist.  */
00035 #define       O_EXCL        0x0800 /* Fail if file already exists.  */
00036 #define       O_TRUNC              0x0400 /* Truncate file to zero length.  */
00037 #define       O_NOCTTY      0x0100 /* Don't assign a controlling terminal.  */
00038 
00039 /* File status flags for `open' and `fcntl'.  */
00040 #define       O_APPEND      0x0008 /* Writes append to the file.  */
00041 #define       O_NONBLOCK    0x0004 /* Non-blocking I/O.  */
00042 
00043 #ifdef __USE_BSD
00044 # define O_NDELAY    O_NONBLOCK
00045 #endif
00046 
00047 /* Mask for file access modes.  This is system-dependent in case
00048    some system ever wants to define some other flavor of access.  */
00049 #define       O_ACCMODE     (O_RDONLY|O_WRONLY|O_RDWR)
00050 
00051 /* Values for the second argument to `fcntl'.  */
00052 #define       F_DUPFD              0      /* Duplicate file descriptor.  */
00053 #define       F_GETFD              1      /* Get file descriptor flags.  */
00054 #define       F_SETFD              2      /* Set file descriptor flags.  */
00055 #define       F_GETFL              3      /* Get file status flags.  */
00056 #define       F_SETFL              4      /* Set file status flags.  */
00057 #if defined __USE_BSD || defined __USE_UNIX98
00058 # define F_GETOWN    5      /* Get owner (receiver of SIGIO).  */
00059 # define F_SETOWN    6      /* Set owner (receiver of SIGIO).  */
00060 #endif
00061 #define       F_GETLK              7      /* Get record locking info.  */
00062 #define       F_SETLK              8      /* Set record locking info.  */
00063 #define       F_SETLKW      9      /* Set record locking info, wait.  */
00064 
00065 /* File descriptor flags used with F_GETFD and F_SETFD.  */
00066 #define       FD_CLOEXEC    1      /* Close on exec.  */
00067 
00068 
00069 #include <bits/types.h>
00070 
00071 /* The structure describing an advisory lock.  This is the type of the third
00072    argument to `fcntl' for the F_GETLK, F_SETLK, and F_SETLKW requests.  */
00073 struct flock
00074   {
00075     short int l_type;       /* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.  */
00076     short int l_whence;     /* Where `l_start' is relative to (like `lseek').  */
00077     __off_t l_start; /* Offset where the lock begins.  */
00078     __off_t l_len;   /* Size of the locked area; zero means until EOF.  */
00079     __pid_t l_pid;   /* Process holding the lock.  */
00080   };
00081 
00082 /* Values for the `l_type' field of a `struct flock'.  */
00083 #define       F_RDLCK       1      /* Read lock.  */
00084 #define       F_WRLCK       2      /* Write lock.  */
00085 #define       F_UNLCK       3      /* Remove lock.  */
00086 
00087 /* Advise to `posix_fadvise'.  */
00088 #ifdef __USE_XOPEN2K
00089 # define POSIX_FADV_NORMAL  0 /* No further special treatment.  */
00090 # define POSIX_FADV_RANDOM  1 /* Expect random page references.  */
00091 # define POSIX_FADV_SEQUENTIAL     2 /* Expect sequential page references.  */
00092 # define POSIX_FADV_WILLNEED       3 /* Will need these pages.  */
00093 # define POSIX_FADV_DONTNEED       4 /* Don't need these pages.  */
00094 # define POSIX_FADV_NOREUSE 5 /* Data will be accessed once.  */
00095 #endif