man2/fstatat.2

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