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+.\" Copyright (c) 1983, 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"     @(#)readlink.2	8.1 (Berkeley) 6/4/93
+.\" $FreeBSD$
+.\"
+.Dd April 10, 2008
+.Dt READLINK 2
+.Os
+.Sh NAME
+.Nm readlink ,
+.Nm readlinkat
+.Nd read value of a symbolic link
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In unistd.h
+.Ft ssize_t
+.Fn readlink "const char *restrict path" "char *restrict buf" "size_t bufsiz"
+.Ft ssize_t
+.Fo readlinkat
+.Fa "int fd" "const char *restrict path" "char *restrict buf" "size_t bufsize"
+.Fc
+.Sh DESCRIPTION
+The
+.Fn readlink
+system call
+places the contents of the symbolic link
+.Fa path
+in the buffer
+.Fa buf ,
+which has size
+.Fa bufsiz .
+The
+.Fn readlink
+system call does not append a
+.Dv NUL
+character to
+.Fa buf .
+.Pp
+The
+.Fn readlinkat
+system call is equivalent to
+.Fn readlink
+except in the case where
+.Fa path
+specifies a relative path.
+In this case the symbolic link whose content is read relative to the
+directory associated with the file descriptor
+.Fa fd
+instead of the current working directory.
+If
+.Fn readlinkat
+is passed the special value
+.Dv AT_FDCWD
+in the
+.Fa fd
+parameter, the current working directory is used and the behavior is
+identical to a call to
+.Fn readlink .
+.Sh RETURN VALUES
+The call returns the count of characters placed in the buffer
+if it succeeds, or a \-1 if an error occurs, placing the error
+code in the global variable
+.Va errno .
+.Sh ERRORS
+The
+.Fn readlink
+system call
+will fail if:
+.Bl -tag -width Er
+.It Bq Er ENOTDIR
+A component of the path prefix is not a directory.
+.It Bq Er ENAMETOOLONG
+A component of a pathname exceeded 255 characters,
+or an entire path name exceeded 1023 characters.
+.It Bq Er ENOENT
+The named file does not exist.
+.It Bq Er EACCES
+Search permission is denied for a component of the path prefix.
+.It Bq Er ELOOP
+Too many symbolic links were encountered in translating the pathname.
+.It Bq Er EINVAL
+The named file is not a symbolic link.
+.It Bq Er EIO
+An I/O error occurred while reading from the file system.
+.It Bq Er EFAULT
+The
+.Fa buf
+argument
+extends outside the process's allocated address space.
+.El
+.Pp
+In addition to the errors returned by the
+.Fn readlink ,
+the
+.Fn readlinkat
+may fail if:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The
+.Fa path
+argument does not specify an absolute path and the
+.Fa fd
+argument is neither
+.Dv AT_FDCWD
+nor a valid file descriptor open for searching.
+.It Bq Er ENOTDIR
+The
+.Fa path
+argument is not an absolute path and
+.Fa fd
+is neither
+.Dv AT_FDCWD
+nor a file descriptor associated with a directory.
+.El
+.Sh SEE ALSO
+.Xr lstat 2 ,
+.Xr stat 2 ,
+.Xr symlink 2 ,
+.Xr symlink 7
+.Sh STANDARDS
+The
+.Fn readlinkat
+system call follows The Open Group Extended API Set 2 specification.
+.Sh HISTORY
+The
+.Fn readlink
+system call appeared in
+.Bx 4.2 .
+The
+.Fn readlinkat
+system call appeared in
+.Fx 8.0 .