1.\" $NetBSD: chroot.2,v 1.8 1997/09/27 19:33:20 hubertf Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)chroot.2 8.1 (Berkeley) 6/4/93 35.\" 36.Dd June 4, 1993 37.Dt CHROOT 2 38.Os BSD 4.2 39.Sh NAME 40.Nm chroot 41.Nd change root directory 42.Sh SYNOPSIS 43.Fd #include <unistd.h> 44.Ft int 45.Fn chroot "const char *dirname" 46.Sh DESCRIPTION 47.Fa Dirname 48is the address of the pathname of a directory, terminated by an ASCII NUL. 49.Fn Chroot 50causes 51.Fa dirname 52to become the root directory, 53that is, the starting point for path searches of pathnames 54beginning with 55.Ql / . 56.Pp 57In order for a directory to become the root directory 58a process must have execute (search) access for that directory. 59.Pp 60It should be noted that 61.Fn chroot 62has no effect on the process's current directory. 63.Pp 64This call is restricted to the super-user. 65.Sh RETURN VALUES 66Upon successful completion, a value of 0 is returned. Otherwise, 67a value of -1 is returned and 68.Va errno 69is set to indicate an error. 70.Sh ERRORS 71.Fn Chroot 72will fail and the root directory will be unchanged if: 73.Bl -tag -width Er 74.It Bq Er ENOTDIR 75A component of the path name is not a directory. 76.It Bq Er ENAMETOOLONG 77A component of a pathname exceeded 78.Dv {NAME_MAX} 79characters, or an entire path name exceeded 80.Dv {PATH_MAX} 81characters. 82.It Bq Er ENOENT 83The named directory does not exist. 84.It Bq Er EACCES 85Search permission is denied for any component of the path name. 86.It Bq Er ELOOP 87Too many symbolic links were encountered in translating the pathname. 88.It Bq Er EFAULT 89.Fa Dirname 90points outside the process's allocated address space. 91.It Bq Er EIO 92An I/O error occurred while reading from or writing to the file system. 93.El 94.Sh SEE ALSO 95.Xr chdir 2 96.Sh HISTORY 97The 98.Fn chroot 99function call appeared in 100.Bx 4.2 . 101