bsd/man/man2/readlink.2

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  34 .\"     @(#)readlink.2  8.1 (Berkeley) 6/4/93
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  36 .Dd June 4, 1993
  37 .Dt READLINK 2
  38 .Os BSD 4.2
  39 .Sh NAME
  40 .Nm readlink
  41 .Nd read value of a symbolic link
  42 .Sh SYNOPSIS
  43 .Fd #include <unistd.h>
  44 .Ft int
  45 .Fn readlink "const char *path" "char *buf" "int bufsiz"
  46 .Sh DESCRIPTION
  47 .Fn Readlink
  48 places the contents of the symbolic link
  49 .Fa path
  50 in the buffer
  51 .Fa buf ,
  52 which has size
  53 .Fa bufsiz .
  54 .Nm Readlink
  55 does not append a
  56 .Dv NUL
  57 character to
  58 .Fa buf .
  59 .Sh RETURN VALUES
  60 The call returns the count of characters placed in the buffer
  61 if it succeeds, or a -1 if an error occurs, placing the error
  62 code in the global variable
  63 .Va errno .
  64 .Sh ERRORS
  65 .Fn Readlink
  66 will fail if:
  67 .Bl -tag -width Er
  68 .It Bq Er ENOTDIR
  69 A component of the path prefix is not a directory.
  70 .It Bq Er ENAMETOOLONG
  71 A component of a pathname exceeded
  72 .Dv {NAME_MAX}
  73 characters, or an entire path name exceeded
  74 .Dv {PATH_MAX}
  75 characters.
  76 .It Bq Er ENOENT
  77 The named file does not exist.
  78 .It Bq Er EACCES
  79 Search permission is denied for a component of the path prefix.
  80 .It Bq Er ELOOP
  81 Too many symbolic links were encountered in translating the pathname.
  82 .It Bq Er EINVAL
  83 The named file is not a symbolic link.
  84 .It Bq Er EIO
  85 An I/O error occurred while reading from the file system.
  86 .It Bq Er EFAULT
  87 .Fa Buf
  88 extends outside the process's allocated address space.
  89 .El
  90 .Sh SEE ALSO
  91 .Xr stat 2 ,
  92 .Xr lstat 2 ,
  93 .Xr symlink 2
  94 .Xr symlink 7 ,
  95 .Sh HISTORY
  96 The
  97 .Fn readlink
  98 function call appeared in
  99 .Bx 4.2 .