man2/fchownat.2

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  26 .TH FCHOWNAT 2 2006-05-05 "Linux" "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 #define _ATFILE_SOURCE
  33 .B #include <unistd.h>
  34 .sp
  35 .BI "int fchownat(int " dirfd ", const char *" pathname ,
  36 .BI "             uid_t " owner ", gid_t " group ", int " flags );
  37 .fi
  38 .SH DESCRIPTION
  39 The
  40 .BR fchownat ()
  41 system call operates in exactly the same way as
  42 .BR chown (2),
  43 except for the differences described in this manual page.
  44
  45 If the pathname given in
  46 .I pathname
  47 is relative, then it is interpreted relative to the directory
  48 referred to by the file descriptor
  49 .I dirfd
  50 (rather than relative to the current working directory of
  51 the calling process, as is done by
  52 .BR chown (2)
  53 for a relative pathname).
  54
  55 If
  56 .I pathname
  57 is relative and
  58 .I dirfd
  59 is the special value
  60 .BR AT_FDCWD ,
  61 then
  62 .I pathname
  63 is interpreted relative to the current working
  64 directory of the calling process (like
  65 .BR chown (2)).
  66
  67 If
  68 .I pathname
  69 is absolute, then
  70 .I dirfd
  71 is ignored.
  72
  73 .I flags
  74 can either be 0, or include the following flag:
  75 .TP
  76 .B AT_SYMLINK_NOFOLLOW
  77 If
  78 .I pathname
  79 is a symbolic link, do not dereference it:
  80 instead operate on the link itself, like
  81 .BR lchown (2).
  82 (By default,
  83 .BR fchownat ()
  84 dereferences symbolic links, like
  85 .BR chown (2).)
  86 .SH "RETURN VALUE"
  87 On success,
  88 .BR fchownat ()
  89 returns 0.
  90 On error, \-1 is returned and
  91 .I errno
  92 is set to indicate the error.
  93 .SH ERRORS
  94 The same errors that occur for
  95 .BR chown (2)
  96 can also occur for
  97 .BR fchownat ().
  98 The following additional errors can occur for
  99 .BR fchownat ():
 100 .TP
 101 .B EBADF
 102 .I dirfd
 103 is not a valid file descriptor.
 104 .TP
 105 .B EINVAL
 106 Invalid flag specified in
 107 .IR flags .
 108 .TP
 109 .B ENOTDIR
 110 .I pathname
 111 is relative and
 112 .I dirfd
 113 is a file descriptor referring to a file other than a directory.
 114 .SH VERSIONS
 115 .BR fchownat ()
 116 was added to Linux in kernel 2.6.16.
 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 NOTES
 122 See
 123 .BR openat (2)
 124 for an explanation of the need for
 125 .BR fchownat ().
 126 .SH "SEE ALSO"
 127 .BR chown (2),
 128 .BR openat (2),
 129 .BR path_resolution (7)