1.\" $OpenBSD: readlink.2,v 1.12 2007/05/31 19:19:33 jmc Exp $ 2.\" $NetBSD: readlink.2,v 1.7 1995/02/27 12:35:54 cgd Exp $ 3.\" 4.\" Copyright (c) 1983, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)readlink.2 8.1 (Berkeley) 6/4/93 32.\" 33.Dd $Mdocdate: May 31 2007 $ 34.Dt READLINK 2 35.Os 36.Sh NAME 37.Nm readlink 38.Nd read value of a symbolic link 39.Sh SYNOPSIS 40.Fd #include <unistd.h> 41.Ft int 42.Fn readlink "const char *path" "char *buf" "size_t bufsiz" 43.Sh DESCRIPTION 44.Fn readlink 45places the contents of the symbolic link 46.Fa path 47in the buffer 48.Fa buf , 49which has size 50.Fa bufsiz . 51.Nm readlink 52does not append a 53.Dv NUL 54character to 55.Fa buf . 56.Sh RETURN VALUES 57The call returns the count of characters placed in the buffer 58if it succeeds, or a \-1 if an error occurs, placing the error 59code in the global variable 60.Va errno . 61.Sh ERRORS 62.Fn readlink 63will fail if: 64.Bl -tag -width Er 65.It Bq Er ENOTDIR 66A component of the path prefix is not a directory. 67.It Bq Er ENAMETOOLONG 68A component of a pathname exceeded 69.Dv {NAME_MAX} 70characters, or an entire path name exceeded 71.Dv {PATH_MAX} 72characters. 73.It Bq Er ENOENT 74The named file does not exist. 75.It Bq Er EACCES 76Search permission is denied for a component of the path prefix. 77.It Bq Er ELOOP 78Too many symbolic links were encountered in translating the pathname. 79.It Bq Er EINVAL 80The named file is not a symbolic link. 81.It Bq Er EIO 82An I/O error occurred while reading from the file system. 83.It Bq Er EFAULT 84.Fa buf 85or 86.Fa path 87extends outside the process's allocated address space. 88.El 89.Sh SEE ALSO 90.Xr lstat 2 , 91.Xr stat 2 , 92.Xr symlink 2 , 93.Xr symlink 7 94.Sh HISTORY 95The 96.Fn readlink 97function call appeared in 98.Bx 4.2 . 99