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glibc  2.9
fcntl.h
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00001 /* O_*, F_*, FD_* bit values for Linux.
00002    Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2004
00003    Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005 
00006    The GNU C Library is free software; you can redistribute it and/or
00007    modify it under the terms of the GNU Lesser General Public
00008    License as published by the Free Software Foundation; either
00009    version 2.1 of the License, or (at your option) any later version.
00010 
00011    The GNU C Library is distributed in the hope that it will be useful,
00012    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014    Lesser General Public License for more details.
00015 
00016    You should have received a copy of the GNU Lesser General Public
00017    License along with the GNU C Library; if not, write to the Free
00018    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00019    02111-1307 USA.  */
00020 
00021 #ifndef       _FCNTL_H
00022 # error "Never use <bits/fcntl.h> directly; include <fcntl.h> instead."
00023 #endif
00024 
00025 
00026 #include <sys/types.h>
00027 
00028 /* open/fcntl - O_SYNC is only implemented on blocks devices and on files
00029    located on an ext2 file system */
00030 #define O_ACCMODE       0003
00031 #define O_RDONLY          00
00032 #define O_WRONLY          01
00033 #define O_RDWR                   02
00034 #define O_CREAT                0100       /* not fcntl */
00035 #define O_EXCL                 0200       /* not fcntl */
00036 #define O_NOCTTY        0400       /* not fcntl */
00037 #define O_TRUNC               01000       /* not fcntl */
00038 #define O_APPEND       02000
00039 #define O_NONBLOCK     04000
00040 #define O_NDELAY     O_NONBLOCK
00041 #define O_SYNC               010000
00042 #define O_FSYNC              O_SYNC
00043 #define O_ASYNC              020000
00044 
00045 #ifdef __USE_GNU
00046 # define O_DIRECT     040000       /* Direct disk access.      */
00047 # define O_DIRECTORY 0200000       /* Must be a directory.      */
00048 # define O_NOFOLLOW  0400000       /* Do not follow links.      */
00049 # define O_NOATIME   01000000 /* Do not set atime.  */
00050 #endif
00051 
00052 /* For now Linux has synchronisity options for data and read operations.
00053    We define the symbols here but let them do the same as O_SYNC since
00054    this is a superset.      */
00055 #if defined __USE_POSIX199309 || defined __USE_UNIX98
00056 # define O_DSYNC     O_SYNC /* Synchronize data.  */
00057 # define O_RSYNC     O_SYNC /* Synchronize read operations.     */
00058 #endif
00059 
00060 #ifdef __USE_LARGEFILE64
00061 # define O_LARGEFILE 0100000
00062 #endif
00063 
00064 /* Values for the second argument to `fcntl'.  */
00065 #define F_DUPFD             0      /* Duplicate file descriptor.  */
00066 #define F_GETFD             1      /* Get file descriptor flags.  */
00067 #define F_SETFD             2      /* Set file descriptor flags.  */
00068 #define F_GETFL             3      /* Get file status flags.  */
00069 #define F_SETFL             4      /* Set file status flags.  */
00070 #ifndef __USE_FILE_OFFSET64
00071 # define F_GETLK     5      /* Get record locking info.  */
00072 # define F_SETLK     6      /* Set record locking info (non-blocking).  */
00073 # define F_SETLKW    7      /* Set record locking info (blocking).    */
00074 #else
00075 # define F_GETLK     F_GETLK64  /* Get record locking info.    */
00076 # define F_SETLK     F_SETLK64  /* Set record locking info (non-blocking).*/
00077 # define F_SETLKW    F_SETLKW64 /* Set record locking info (blocking).  */
00078 #endif
00079 #define F_GETLK64    12     /* Get record locking info.  */
00080 #define F_SETLK64    13     /* Set record locking info (non-blocking).  */
00081 #define F_SETLKW64   14     /* Set record locking info (blocking).    */
00082 
00083 #if defined __USE_BSD || defined __USE_UNIX98
00084 # define F_SETOWN    8      /* Get owner of socket (receiver of SIGIO).  */
00085 # define F_GETOWN    9      /* Set owner of socket (receiver of SIGIO).  */
00086 #endif
00087 
00088 #ifdef __USE_GNU
00089 # define F_SETSIG    10     /* Set number of signal to be sent.  */
00090 # define F_GETSIG    11     /* Get number of signal to be sent.  */
00091 #endif
00092 
00093 #ifdef __USE_GNU
00094 # define F_SETLEASE  1024   /* Set a lease.       */
00095 # define F_GETLEASE  1025   /* Enquire what lease is active.  */
00096 # define F_NOTIFY    1026   /* Request notfications on a directory.    */
00097 # define F_DUPFD_CLOEXEC 1030      /* Duplicate file descriptor with
00098                                close-on-exit set.  */
00099 #endif
00100 
00101 /* For F_[GET|SET]FD.  */
00102 #define FD_CLOEXEC   1      /* actually anything with low bit set goes */
00103 
00104 /* For posix fcntl() and `l_type' field of a `struct flock' for lockf().  */
00105 #define F_RDLCK             0      /* Read lock.  */
00106 #define F_WRLCK             1      /* Write lock.       */
00107 #define F_UNLCK             2      /* Remove lock.       */
00108 
00109 /* For old implementation of bsd flock().  */
00110 #define F_EXLCK             4      /* or 3 */
00111 #define F_SHLCK             8      /* or 4 */
00112 
00113 #ifdef __USE_BSD
00114 /* Operations for bsd flock(), also used by the kernel implementation.       */
00115 # define LOCK_SH     1      /* shared lock */
00116 # define LOCK_EX     2      /* exclusive lock */
00117 # define LOCK_NB     4      /* or'd with one of the above to prevent
00118                                blocking */
00119 # define LOCK_UN     8      /* remove lock */
00120 #endif
00121 
00122 #ifdef __USE_GNU
00123 # define LOCK_MAND   32     /* This is a mandatory flock:      */
00124 # define LOCK_READ   64     /* ... which allows concurrent read operations.   */
00125 # define LOCK_WRITE  128    /* ... which allows concurrent write operations.  */
00126 # define LOCK_RW     192    /* ... Which allows concurrent read & write operations.  */
00127 #endif
00128 
00129 #ifdef __USE_GNU
00130 /* Types of directory notifications that may be requested with F_NOTIFY.  */
00131 # define DN_ACCESS   0x00000001    /* File accessed.  */
00132 # define DN_MODIFY   0x00000002    /* File modified.  */
00133 # define DN_CREATE   0x00000004    /* File created.  */
00134 # define DN_DELETE   0x00000008    /* File removed.  */
00135 # define DN_RENAME   0x00000010    /* File renamed.  */
00136 # define DN_ATTRIB   0x00000020    /* File changed attibutes.  */
00137 # define DN_MULTISHOT       0x80000000    /* Don't remove notifier.  */
00138 #endif
00139 
00140 struct flock
00141   {
00142     short int l_type;       /* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.   */
00143     short int l_whence;     /* Where `l_start' is relative to (like `lseek').  */
00144 #ifndef __USE_FILE_OFFSET64
00145     __off_t l_start; /* Offset where the lock begins.  */
00146     __off_t l_len;   /* Size of the locked area; zero means until EOF.  */
00147 #else
00148     __off64_t l_start;      /* Offset where the lock begins.  */
00149     __off64_t l_len; /* Size of the locked area; zero means until EOF.  */
00150 #endif
00151     __pid_t l_pid;   /* Process holding the lock.  */
00152   };
00153 
00154 #ifdef __USE_LARGEFILE64
00155 struct flock64
00156   {
00157     short int l_type;       /* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.   */
00158     short int l_whence;     /* Where `l_start' is relative to (like `lseek').  */
00159     __off64_t l_start;      /* Offset where the lock begins.  */
00160     __off64_t l_len; /* Size of the locked area; zero means until EOF.  */
00161     __pid_t l_pid;   /* Process holding the lock.  */
00162   };
00163 #endif
00164 
00165 /* Define some more compatibility macros to be backward compatible with
00166    BSD systems which did not managed to hide these kernel macros.  */
00167 #ifdef __USE_BSD
00168 # define FAPPEND     O_APPEND
00169 # define FFSYNC             O_FSYNC
00170 # define FASYNC             O_ASYNC
00171 # define FNONBLOCK   O_NONBLOCK
00172 # define FNDELAY     O_NDELAY
00173 #endif /* Use BSD.  */
00174 
00175 /* Advise to `posix_fadvise'.  */
00176 #ifdef __USE_XOPEN2K
00177 # define POSIX_FADV_NORMAL  0 /* No further special treatment.  */
00178 # define POSIX_FADV_RANDOM  1 /* Expect random page references.  */
00179 # define POSIX_FADV_SEQUENTIAL     2 /* Expect sequential page references.    */
00180 # define POSIX_FADV_WILLNEED       3 /* Will need these pages.  */
00181 # define POSIX_FADV_DONTNEED       4 /* Don't need these pages.  */
00182 # define POSIX_FADV_NOREUSE 5 /* Data will be accessed once.  */
00183 #endif
00184 
00185 __BEGIN_DECLS
00186 
00187 /* Provide kernel hint to read ahead.  */
00188 extern ssize_t readahead (int __fd, __off64_t __offset, size_t __count)
00189     __THROW;
00190 
00191 __END_DECLS