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CHROOT(2)		  FreeBSD System Calls Manual		     CHROOT(2)

NAME
     chroot -- change root directory

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     chroot(const char *dirname);

DESCRIPTION
     Dirname is	the address of the pathname of a directory, terminated by an
     ASCII NUL.	 Chroot() causes dirname to become the root directory, that
     is, the starting point for	path searches of pathnames beginning with `/'.

     In	order for a directory to become	the root directory a process must have
     execute (search) access for that directory.

     It	should be noted	that chroot() has no effect on the process's current
     directory.

     This call is restricted to	the super-user.

     Depending on the setting of the `kern.chroot_allow_open_directories'
     sysctl variable, open filedescriptors which reference directories will
     make the chroot() fail as follows:

     If	`kern.chroot_allow_open_directories' is	set to zero, chroot() will
     always fail with EPERM if there are any directories open.

     If	`kern.chroot_allow_open_directories' is	set to one (the	default),
     chroot() will fail	with EPERM if there are	any directories	open and the
     process is	already	subject	to a chroot() call.

     Any other value for `kern.chroot_allow_open_directories' will bypass the
     check for open directories

     Upon successful completion, a value of 0 is returned.  Otherwise, a value
     of	-1 is returned and errno is set	to indicate an error.

ERRORS
     Chroot() will fail	and the	root directory will be unchanged if:

     [ENOTDIR]		A component of the path	name is	not a directory.

     [EPERM]		The effective user ID is not the super-user, or	one or
			more filedescriptors are open directories.

     [ENAMETOOLONG]	A component of a pathname exceeded 255 characters, or
			an entire path name exceeded 1023 characters.

     [ENOENT]		The named directory does not exist.

     [EACCES]		Search permission is denied for	any component of the
			path name.

     [ELOOP]		Too many symbolic links	were encountered in translat-
			ing the	pathname.

     [EFAULT]		dirname	points outside the process's allocated address
			space.

     [EIO]		An I/O error occurred while reading from or writing to
			the file system.

SEE ALSO
     chdir(2), jail(2)

HISTORY
     The chroot() function call	appeared in 4.2BSD.

FreeBSD	9.3			 June 4, 1993			   FreeBSD 9.3

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ERRORS | SEE ALSO | HISTORY

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