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Manual Reference Pages  - CHROOT (2)

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chroot - change root directory

CONTENTS

Synopsis
Description
Errors
Notes

#include <unistd.h>

int chroot(const char *path);

chroot changes the root directory to that specified in path. This directory will be used for path names beginning with /. The root directory is inherited by all children of the current process.

Only the super-user may change the root directory.

Note that this call does not change the current working directory, so that ‘.’ can be outside the tree rooted at ‘/’. In particular, the super-user can escape from a ‘chroot jail’ by doing ‘mkdir foo; chroot foo; cd ..’.

On success, zero is returned. On error, -1 is returned, and errno is set appropriately.

Depending on the file system, other errors can be returned. The more general errors are listed below:

EPERM	The effective UID is not zero.
EFAULT	path points outside your accessible address space.
ENAMETOOLONG
	path is too long.
ENOENT	The file does not exist.
ENOMEM	Insufficient kernel memory was available.
ENOTDIR
	A component of path is not a directory.
EACCES	Search permission is denied on a component of the path prefix.
ELOOP	Too many symbolic links were encountered in resolving path.
EIO	An I/O error occurred.

SVr4, SVID, 4.4BSD, X/OPEN. This function is not part of POSIX.1. SVr4 documents additional EINTR, ENOLINK and EMULTIHOP error conditions. X/OPEN does not document EIO, ENOMEM or EFAULT error conditions. This interface is marked as legacy by X/OPEN.

FreeBSD has a stronger jail() system call.

chdir(2)

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