chroot()

Change the root directory

Synopsis:

#include <unistd.h>

int chroot( const char *path );

Arguments:

path: The name of the new root directory.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The chroot() function causes the path directory to become the root directory, the starting point for path searches for path names beginning with /. The user's working directory is unaffected.

The .. entry in the root directory is interpreted to mean the root directory itself. Thus, you can't use .. to access files outside the subtree rooted at the root directory.

Returns:

0: Success.
-1: An error occurred; errno is set.

Errors:

EACCES: Search permission is denied for a component of path.
EBADF: The descriptor isn't valid.
EFAULT: The path argument points to an illegal address.
EINTR: A signal was caught during the chroot() function.
EIO: An I/O error occurred while reading from or writing to the filesystem.
ELOOP: Too many symbolic links were encountered in translating path.
EMULTIHOP: Components of path require hopping to multiple remote machines, and the filesystem type doesn't allow it.
ENAMETOOLONG: The length of the path argument exceeds {PATH_MAX}, or the length of a path component exceeds {NAME_MAX} while {_POSIX_NO_TRUNC} is in effect.
ENOENT: The named directory doesn't exist or is a null pathname.
ENOLINK: The path points to a remote machine and the link to that machine is no longer active.
ENOTDIR: Any component of the path name isn't a directory.
EPERM: The effective user of the calling process isn't the superuser.

Classification:

Legacy Unix

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes