1.\" Copyright (c) 1994 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Jan-Simon Pendry. 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.\" 4. 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.\" @(#)realpath.3 8.2 (Berkeley) 2/16/94 32.\" $FreeBSD$ 33.\" 34.Dd February 16, 1994 35.Dt REALPATH 3 36.Os 37.Sh NAME 38.Nm realpath 39.Nd returns the canonicalized absolute pathname 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In sys/param.h 44.In stdlib.h 45.Ft "char *" 46.Fn realpath "const char *pathname" "char resolved_path[PATH_MAX]" 47.Sh DESCRIPTION 48The 49.Fn realpath 50function resolves all symbolic links, extra 51.Dq / 52characters and references to 53.Pa /./ 54and 55.Pa /../ 56in 57.Fa pathname , 58and copies the resulting absolute pathname into 59the memory referenced by 60.Fa resolved_path . 61The 62.Fa resolved_path 63argument 64.Em must 65refer to a buffer capable of storing at least 66.Dv PATH_MAX 67characters. 68.Pp 69The 70.Fn realpath 71function will resolve both absolute and relative paths 72and return the absolute pathname corresponding to 73.Fa pathname . 74All but the last component of 75.Fa pathname 76must exist when 77.Fn realpath 78is called. 79.Sh "RETURN VALUES" 80The 81.Fn realpath 82function returns 83.Fa resolved_path 84on success. 85If an error occurs, 86.Fn realpath 87returns 88.Dv NULL , 89and 90.Fa resolved_path 91contains the pathname which caused the problem. 92.Sh ERRORS 93The function 94.Fn realpath 95may fail and set the external variable 96.Va errno 97for any of the errors specified for the library functions 98.Xr lstat 2 , 99.Xr readlink 2 100and 101.Xr getcwd 3 . 102.Sh CAVEATS 103This implementation of 104.Fn realpath 105differs slightly from the Solaris implementation. 106The 107.Bx 4.4 108version always returns absolute pathnames, 109whereas the Solaris implementation will, 110under certain circumstances, return a relative 111.Fa resolved_path 112when given a relative 113.Fa pathname . 114.Sh "SEE ALSO" 115.Xr getcwd 3 116.Sh HISTORY 117The 118.Fn realpath 119function first appeared in 120.Bx 4.4 . 121