man2/fchownat.2

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  26 .TH FCHOWNAT 2 2006-05-05 "Linux 2.6.16" "Linux Programmer's Manual"
  27 .SH NAME
  28 fchownat \- change ownership of a file relative to a directory \
  29 file descriptor
  30 .SH SYNOPSIS
  31 .nf
  32 .B #include <unistd.h>
  33 .sp
  34 .BI "int fchownat(int " dirfd ", const char *" path ,
  35 .BI "             uid_t " owner ", gid_t " group ", int " flags );
  36 .fi
  37 .SH DESCRIPTION
  38 The
  39 .BR fchownat ()
  40 system call operates in exactly the same way as
  41 .BR chown (2),
  42 except for the differences described in this manual page.
  43
  44 If the pathname given in
  45 .I path
  46 is relative, then it is interpreted relative to the directory
  47 referred to by the file descriptor
  48 .IR dirfd
  49 (rather than relative to the current working directory of
  50 the calling process, as is done by
  51 .BR chown (2)
  52 for a relative pathname).
  53
  54 If the pathname given in
  55 .I path
  56 is relative and
  57 .I dirfd
  58 is the special value
  59 .BR AT_FDCWD ,
  60 then
  61 .I path
  62 is interpreted relative to the current working
  63 directory of the calling process (like
  64 .BR chown (2)).
  65
  66 If the pathname given in
  67 .IR path
  68 is absolute, then
  69 .I dirfd
  70 is ignored.
  71
  72 .I flags
  73 can either be 0, or include the following flag:
  74 .TP
  75 .B AT_SYMLINK_NOFOLLOW
  76 If
  77 .I path
  78 is a symbolic link, do not dereference it:
  79 instead return information about the link itself, like
  80 .BR lchown (2).
  81 (By default,
  82 .BR fchownat ()
  83 dereferences symbolic links, like
  84 .BR chown (2).)
  85 .SH "RETURN VALUE"
  86 On success,
  87 .BR fchownat ()
  88 returns 0.
  89 On error, \-1 is returned and
  90 .I errno
  91 is set to indicate the error.
  92 .SH ERRORS
  93 The same errors that occur for
  94 .BR chown (2)
  95 can also occur for
  96 .BR fchownat ().
  97 The following additional errors can occur for
  98 .BR fchownat ():
  99 .TP
 100 .B EBADF
 101 .I dirfd
 102 is not a valid file descriptor.
 103 .TP
 104 .B EINVAL
 105 Invalid flag specified in
 106 .IR flags .
 107 .TP
 108 .B ENOTDIR
 109 .I path
 110 is a relative path and
 111 .I dirfd
 112 is a file descriptor referring to a file other than a directory.
 113 .SH NOTES
 114 See
 115 .BR openat (2)
 116 for an explanation of the need for
 117 .BR fchownat ().
 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 VERSIONS
 123 .BR fchownat ()
 124 was added to Linux in kernel 2.6.16.
 125 .SH "SEE ALSO"
 126 .BR chown (2),
 127 .BR openat (2),
 128 .BR path_resolution (2)