man2/fstatat.2

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  26 .TH FSTATAT 2 2006-04-30 "Linux" "Linux Programmer's Manual"
  27 .SH NAME
  28 fstatat \- get file status relative to a directory file descriptor
  29 .SH SYNOPSIS
  30 .nf
  31 .B #define _ATFILE_SOURCE
  32 .B #include <fcntl.h>           /* Definition of AT_* constants */
  33 .B #include <sys/stat.h>
  34 .sp
  35 .BI "int fstatat(int " dirfd ", const char *" pathname ", struct stat *" \
  36 buf ,
  37 .BI "            int " flags );
  38 .fi
  39 .SH DESCRIPTION
  40 The
  41 .BR fstatat ()
  42 system call operates in exactly the same way as
  43 .BR stat (2),
  44 except for the differences described in this manual page.
  45
  46 If the pathname given in
  47 .I pathname
  48 is relative, then it is interpreted relative to the directory
  49 referred to by the file descriptor
  50 .I dirfd
  51 (rather than relative to the current working directory of
  52 the calling process, as is done by
  53 .BR stat (2)
  54 for a relative pathname).
  55
  56 If
  57 .I pathname
  58 is relative and
  59 .I dirfd
  60 is the special value
  61 .BR AT_FDCWD ,
  62 then
  63 .I pathname
  64 is interpreted relative to the current working
  65 directory of the calling process (like
  66 .BR stat (2)).
  67
  68 If
  69 .I pathname
  70 is absolute, then
  71 .I dirfd
  72 is ignored.
  73
  74 .I flags
  75 can either be 0, or include the following flag:
  76 .TP
  77 .B AT_SYMLINK_NOFOLLOW
  78 If
  79 .I pathname
  80 is a symbolic link, do not dereference it:
  81 instead return information about the link itself, like
  82 .BR lstat (2).
  83 (By default,
  84 .BR fstatat ()
  85 dereferences symbolic links, like
  86 .BR stat (2).)
  87 .SH "RETURN VALUE"
  88 On success,
  89 .BR fstatat ()
  90 returns 0.
  91 On error, \-1 is returned and
  92 .I errno
  93 is set to indicate the error.
  94 .SH ERRORS
  95 The same errors that occur for
  96 .BR stat (2)
  97 can also occur for
  98 .BR fstatat ().
  99 The following additional errors can occur for
 100 .BR fstatat ():
 101 .TP
 102 .B EBADF
 103 .I dirfd
 104 is not a valid file descriptor.
 105 .TP
 106 .B EINVAL
 107 Invalid flag specified in
 108 .IR flags .
 109 .TP
 110 .B ENOTDIR
 111 .I pathname
 112 is relative and
 113 .I dirfd
 114 is a file descriptor referring to a file other than a directory.
 115 .SH VERSIONS
 116 .BR fstatat ()
 117 was added to Linux in kernel 2.6.16.
 118 .SH "CONFORMING TO"
 119 This system call is non-standard but is proposed
 120 for inclusion in a future revision of POSIX.1.
 121 A similar system call exists on Solaris.
 122 .SH NOTES
 123 See
 124 .BR openat (2)
 125 for an explanation of the need for
 126 .BR fstatat ().
 127 .SH "SEE ALSO"
 128 .BR openat (2),
 129 .BR stat (2),
 130 .BR path_resolution (7),
 131 .BR symlink (7)