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.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)realpath.3 8.2 (Berkeley) 2/16/94 36.\" $FreeBSD$ 37.\" 38.Dd February 16, 1994 39.Dt REALPATH 3 40.Os 41.Sh NAME 42.Nm realpath 43.Nd returns the canonicalized absolute pathname 44.Sh SYNOPSIS 45.Fd #include <sys/param.h> 46.Fd #include <stdlib.h> 47.Ft "char *" 48.Fn realpath "const char *pathname" "char resolved_path[MAXPATHLEN]" 49.Sh DESCRIPTION 50The 51.Fn realpath 52function resolves all symbolic links, extra 53.Dq / 54characters and references to 55.Pa /./ 56and 57.Pa /../ 58in 59.Fa pathname , 60and copies the resulting absolute pathname into 61the memory referenced by 62.Fa resolved_path . 63The 64.Fa resolved_path 65argument 66.Em must 67refer to a buffer capable of storing at least 68.Dv MAXPATHLEN 69characters. 70.Pp 71The 72.Fn realpath 73function will resolve both absolute and relative paths 74and return the absolute pathname corresponding to 75.Fa pathname . 76All but the last component of 77.Fa pathname 78must exist when 79.Fn realpath 80is called. 81.Sh "RETURN VALUES" 82The 83.Fn realpath 84function returns 85.Fa resolved_path 86on success. 87If an error occurs, 88.Fn realpath 89returns 90.Dv NULL , 91and 92.Fa resolved_path 93contains the pathname which caused the problem. 94.Sh ERRORS 95The function 96.Fn realpath 97may fail and set the external variable 98.Va errno 99for any of the errors specified for the library functions 100.Xr chdir 2 , 101.Xr close 2 , 102.Xr fchdir 2 , 103.Xr lstat 2 , 104.Xr open 2 , 105.Xr readlink 2 106and 107.Xr getcwd 3 . 108.Sh CAVEATS 109This implementation of 110.Fn realpath 111differs slightly from the Solaris implementation. 112The 113.Bx 4.4 114version always returns absolute pathnames, 115whereas the Solaris implementation will, 116under certain circumstances, return a relative 117.Fa resolved_path 118when given a relative 119.Fa pathname . 120.Sh "SEE ALSO" 121.Xr getcwd 3 122.Sh HISTORY 123The 124.Fn realpath 125function call first appeared in 126.Bx 4.4 . 127