io/fcntl.h

   1 /* Copyright (C) 1991,1992,1994-2001,2003,2004 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 /*
  20  *      POSIX Standard: 6.5 File Control Operations     <fcntl.h>
  21  */
  22
  23 #ifndef _FCNTL_H
  24 #define _FCNTL_H        1
  25
  26 #include <features.h>
  27
  28 /* This must be early so <bits/fcntl.h> can define types winningly.  */
  29 __BEGIN_DECLS
  30
  31 /* Get the definitions of O_*, F_*, FD_*: all the
  32    numbers and flag bits for `open', `fcntl', et al.  */
  33 #include <bits/fcntl.h>
  34
  35 /* For XPG all symbols from <sys/stat.h> should also be available.  */
  36 #ifdef __USE_XOPEN
  37 # include <sys/stat.h>
  38 #endif
  39
  40 #ifdef  __USE_MISC
  41 # ifndef R_OK                   /* Verbatim from <unistd.h>.  Ugh.  */
  42 /* Values for the second argument to access.
  43    These may be OR'd together.  */
  44 #  define R_OK  4               /* Test for read permission.  */
  45 #  define W_OK  2               /* Test for write permission.  */
  46 #  define X_OK  1               /* Test for execute permission.  */
  47 #  define F_OK  0               /* Test for existence.  */
  48 # endif
  49 #endif /* Use misc.  */
  50
  51 /* XPG wants the following symbols.  */
  52 #ifdef __USE_XOPEN              /* <stdio.h> has the same definitions.  */
  53 # define SEEK_SET       0       /* Seek from beginning of file.  */
  54 # define SEEK_CUR       1       /* Seek from current position.  */
  55 # define SEEK_END       2       /* Seek from end of file.  */
  56 #endif  /* XPG */
  57
  58 /* Do the file control operation described by CMD on FD.
  59    The remaining arguments are interpreted depending on CMD.
  60
  61    This function is a cancellation point and therefore not marked with
  62    __THROW.  */
  63 extern int fcntl (int __fd, int __cmd, ...);
  64
  65 /* Open FILE and return a new file descriptor for it, or -1 on error.
  66    OFLAG determines the type of access used.  If O_CREAT is on OFLAG,
  67    the third argument is taken as a `mode_t', the mode of the created file.
  68
  69    This function is a cancellation point and therefore not marked with
  70    __THROW.  */
  71 #ifndef __USE_FILE_OFFSET64
  72 extern int open (__const char *__file, int __oflag, ...);
  73 #else
  74 # ifdef __REDIRECT
  75 extern int __REDIRECT (open, (__const char *__file, int __oflag, ...), open64);
  76 # else
  77 #  define open open64
  78 # endif
  79 #endif
  80 #ifdef __USE_LARGEFILE64
  81 extern int open64 (__const char *__file, int __oflag, ...);
  82 #endif
  83
  84 /* Create and open FILE, with mode MODE.  This takes an `int' MODE
  85    argument because that is what `mode_t' will be widened to.
  86
  87    This function is a cancellation point and therefore not marked with
  88    __THROW.  */
  89 #ifndef __USE_FILE_OFFSET64
  90 extern int creat (__const char *__file, __mode_t __mode);
  91 #else
  92 # ifdef __REDIRECT
  93 extern int __REDIRECT (creat, (__const char *__file, __mode_t __mode),
  94                        creat64);
  95 # else
  96 #  define creat creat64
  97 # endif
  98 #endif
  99 #ifdef __USE_LARGEFILE64
 100 extern int creat64 (__const char *__file, __mode_t __mode);
 101 #endif
 102
 103 #if !defined F_LOCK && (defined __USE_MISC || (defined __USE_XOPEN_EXTENDED \
 104                                                && !defined __USE_POSIX))
 105 /* NOTE: These declarations also appear in <unistd.h>; be sure to keep both
 106    files consistent.  Some systems have them there and some here, and some
 107    software depends on the macros being defined without including both.  */
 108
 109 /* `lockf' is a simpler interface to the locking facilities of `fcntl'.
 110    LEN is always relative to the current file position.
 111    The CMD argument is one of the following.  */
 112
 113 # define F_ULOCK 0      /* Unlock a previously locked region.  */
 114 # define F_LOCK  1      /* Lock a region for exclusive use.  */
 115 # define F_TLOCK 2      /* Test and lock a region for exclusive use.  */
 116 # define F_TEST  3      /* Test a region for other processes locks.  */
 117
 118 # ifndef __USE_FILE_OFFSET64
 119 extern int lockf (int __fd, int __cmd, __off_t __len);
 120 # else
 121 # ifdef __REDIRECT
 122 extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len), lockf64);
 123 # else
 124 #  define lockf lockf64
 125 # endif
 126 # endif
 127 # ifdef __USE_LARGEFILE64
 128 extern int lockf64 (int __fd, int __cmd, __off64_t __len);
 129 # endif
 130 #endif
 131
 132 #ifdef __USE_XOPEN2K
 133 /* Advice the system about the expected behaviour of the application with
 134    respect to the file associated with FD.  */
 135 # ifndef __USE_FILE_OFFSET64
 136 extern int posix_fadvise (int __fd, __off_t __offset, __off_t __len,
 137                           int __advise) __THROW;
 138 # else
 139 # ifdef __REDIRECT_NTH
 140 extern int __REDIRECT_NTH (posix_fadvise, (int __fd, __off64_t __offset,
 141                                            __off64_t __len, int __advise),
 142                            posix_fadvise64);
 143 # else
 144 #  define posix_fadvise posix_fadvise64
 145 # endif
 146 # endif
 147 # ifdef __USE_LARGEFILE64
 148 extern int posix_fadvise64 (int __fd, __off64_t __offset, __off64_t __len,
 149                             int __advise) __THROW;
 150 # endif
 151
 152
 153 /* Reserve storage for the data of the file associated with FD.
 154
 155    This function is a possible cancellation points and therefore not
 156    marked with __THROW.  */
 157 # ifndef __USE_FILE_OFFSET64
 158 extern int posix_fallocate (int __fd, __off_t __offset, __off_t __len);
 159 # else
 160 # ifdef __REDIRECT
 161 extern int __REDIRECT (posix_fallocate, (int __fd, __off64_t __offset,
 162                                          __off64_t __len),
 163                        posix_fallocate64);
 164 # else
 165 #  define posix_fallocate posix_fallocate64
 166 # endif
 167 # endif
 168 # ifdef __USE_LARGEFILE64
 169 extern int posix_fallocate64 (int __fd, __off64_t __offset, __off64_t __len);
 170 # endif
 171 #endif
 172
 173 __END_DECLS
 174
 175 #endif /* fcntl.h  */