1.\" Copyright (c) 1983, 1991 Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" from: @(#)chroot.2 6.5 (Berkeley) 3/10/91 33.\" $Id: chroot.2,v 1.6 1994/04/22 00:13:31 jtc Exp $ 34.\" 35.Dd March 10, 1991 36.Dt CHROOT 2 37.Os BSD 4.2 38.Sh NAME 39.Nm chroot 40.Nd change root directory 41.Sh SYNOPSIS 42.Fd #include <unistd.h> 43.Ft int 44.Fn chroot "const char *dirname" 45.Sh DESCRIPTION 46.Fa Dirname 47is the address of the pathname of a directory, terminated by an ASCII NUL. 48.Fn Chroot 49causes 50.Fa dirname 51to become the root directory, 52that is, the starting point for path searches of pathnames 53beginning with 54.Ql / . 55.Pp 56In order for a directory to become the root directory 57a process must have execute (search) access for that directory. 58.Pp 59It should be noted that 60.Fn chroot 61has no effect on the process's current directory. 62.Pp 63This call is restricted to the super-user. 64.Sh RETURN VALUES 65Upon successful completion, a value of 0 is returned. Otherwise, 66a value of -1 is returned and 67.Va errno 68is set to indicate an error. 69.Sh ERRORS 70.Fn Chroot 71will fail and the root directory will be unchanged if: 72.Bl -tag -width Er 73.It Bq Er ENOTDIR 74A component of the path name is not a directory. 75.It Bq Er ENAMETOOLONG 76A component of a pathname exceeded 77.Dv {NAME_MAX} 78characters, or an entire path name exceeded 79.Dv {PATH_MAX} 80characters. 81.It Bq Er ENOENT 82The named directory does not exist. 83.It Bq Er EACCES 84Search permission is denied for any component of the path name. 85.It Bq Er ELOOP 86Too many symbolic links were encountered in translating the pathname. 87.It Bq Er EFAULT 88.Fa Path 89points outside the process's allocated address space. 90.It Bq Er EIO 91An I/O error occurred while reading from or writing to the file system. 92.El 93.Sh SEE ALSO 94.Xr chdir 2 95.Sh HISTORY 96The 97.Fn chroot 98function call appeared in 99.Bx 4.2 . 100