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 LIBRARY 45.Lb libc 46.Sh SYNOPSIS 47.In sys/param.h 48.In stdlib.h 49.Ft "char *" 50.Fn realpath "const char *pathname" "char resolved_path[PATH_MAX]" 51.Sh DESCRIPTION 52The 53.Fn realpath 54function resolves all symbolic links, extra 55.Dq / 56characters and references to 57.Pa /./ 58and 59.Pa /../ 60in 61.Fa pathname , 62and copies the resulting absolute pathname into 63the memory referenced by 64.Fa resolved_path . 65The 66.Fa resolved_path 67argument 68.Em must 69refer to a buffer capable of storing at least 70.Dv PATH_MAX 71characters. 72.Pp 73The 74.Fn realpath 75function will resolve both absolute and relative paths 76and return the absolute pathname corresponding to 77.Fa pathname . 78All but the last component of 79.Fa pathname 80must exist when 81.Fn realpath 82is called. 83.Sh "RETURN VALUES" 84The 85.Fn realpath 86function returns 87.Fa resolved_path 88on success. 89If an error occurs, 90.Fn realpath 91returns 92.Dv NULL , 93and 94.Fa resolved_path 95contains the pathname which caused the problem. 96.Sh ERRORS 97The function 98.Fn realpath 99may fail and set the external variable 100.Va errno 101for any of the errors specified for the library functions 102.Xr lstat 2 , 103.Xr readlink 2 104and 105.Xr getcwd 3 . 106.Sh CAVEATS 107This implementation of 108.Fn realpath 109differs slightly from the Solaris implementation. 110The 111.Bx 4.4 112version always returns absolute pathnames, 113whereas the Solaris implementation will, 114under certain circumstances, return a relative 115.Fa resolved_path 116when given a relative 117.Fa pathname . 118.Sh "SEE ALSO" 119.Xr getcwd 3 120.Sh HISTORY 121The 122.Fn realpath 123function first appeared in 124.Bx 4.4 . 125