man2/symlinkat.2

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  26 .TH SYMLINKAT 2 2006-04-10 "Linux" "Linux Programmer's Manual"
  27 .SH NAME
  28 symlinkat \- create a symbolic link 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 <stdio.h>
  34 .sp
  35 .BI "int symlinkat(const char *" oldpath ", int " newdirfd \
  36 ", const char *" newpath );
  37 .fi
  38 .SH DESCRIPTION
  39 The
  40 .BR symlinkat ()
  41 system call operates in exactly the same way as
  42 .BR symlink (2),
  43 except for the differences described in this manual page.
  44
  45 If the pathname given in
  46 .I newpath
  47 is relative, then it is interpreted relative to the directory
  48 referred to by the file descriptor
  49 .I newdirfd
  50 (rather than relative to the current working directory of
  51 the calling process, as is done by
  52 .BR symlink (2)
  53 for a relative pathname).
  54
  55 If
  56 .I newpath
  57 is relative and
  58 .I newdirfd
  59 is the special value
  60 .BR AT_FDCWD ,
  61 then
  62 .I newpath
  63 is interpreted relative to the current working
  64 directory of the calling process (like
  65 .BR symlink (2)).
  66
  67 If
  68 .I newpath
  69 is absolute, then
  70 .I newdirfd
  71 is ignored.
  72 .SH "RETURN VALUE"
  73 On success,
  74 .BR symlinkat ()
  75 returns 0.
  76 On error, \-1 is returned and
  77 .I errno
  78 is set to indicate the error.
  79 .SH ERRORS
  80 The same errors that occur for
  81 .BR symlink (2)
  82 can also occur for
  83 .BR symlinkat ().
  84 The following additional errors can occur for
  85 .BR symlinkat ():
  86 .TP
  87 .B EBADF
  88 .I newdirfd
  89 is not a valid file descriptor.
  90 .TP
  91 .B ENOTDIR
  92 .I newpath
  93 is relative and
  94 .I newdirfd
  95 is a file descriptor referring to a file other than a directory.
  96 .SH VERSIONS
  97 .BR symlinkat ()
  98 was added to Linux in kernel 2.6.16.
  99 .SH "CONFORMING TO"
 100 This system call is non-standard but is proposed
 101 for inclusion in a future revision of POSIX.1.
 102 .SH NOTES
 103 See
 104 .BR openat (2)
 105 for an explanation of the need for
 106 .BR symlinkat ().
 107 .SH "SEE ALSO"
 108 .BR openat (2),
 109 .BR symlink (2),
 110 .BR path_resolution (7),
 111 .BR symlink (7)