fakechroot man page on Scientific

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       fakechroot - gives a fake chroot environment

       fakechroot [-s|--use-system-libs] [-l|--lib library] [--] [command]

       fakechroot runs a command in an environment were is additional
       possibility to use chroot(8) command without root privileges.  This is
       useful for allowing users to create own chrooted environment with
       possibility to install another packages without need for root

       fakechroot replaces more library functions (chroot(2), open(2), etc.)
       by ones that simulate the effect the real library functions would have
       had, had the user really been in chroot.	 These wrapper functions are
       in a shared library /usr/lib/fakechroot/libfakechroot.so which is
       loaded through the LD_PRELOAD mechanism of the dynamic loader.  (See

       In fake chroot you can install Debian bootstrap with `debootstrap
       --variant=fakechroot' command.  In this environment you can use i.e.
       apt-get(8) command to install another packages from common user's

       In the current version, the fakechroot does not provide the fakeroot(1)
       functionality! You might to call fakechroot with fakeroot command, if
       you want to emulate root environment, i.e.:

	$ fakeroot fakechroot /usr/sbin/chroot /tmp/debian /bin/sh
	# id
	uid=0(root) gid=0(root) groups=0(root)

       -l library|--lib library
	   Specify an alternative wrapper library.

	   Use system libraries before chroot's libraries.  This might be a
	   workaround if system dynamic linker (/lib/ld-linux.so.2 for Linux)
	   can not load libc.so from fake chroot.

	   Try this setting if you noticed following errors:

	    $ fakechroot /usr/sbin/chroot /tmp/sarge /bin/true
	    /bin/true: relocation error: /srv/sarge/lib/tls/libc.so.6: symbol _dl
	    _starting_up, version GLIBC_PRIVATE not defined in file ld-linux.so.2
	     with link time reference

	    $ fakechroot /usr/sbin/chroot /tmp/centos4 /bin/true
	    Segmentation fault

       [--] command
	   Any command you want to be ran as fakechroot.  Use '--' if in the
	   command you have other options that may confuse fakechroot's option

       -h  Display help.

       -v  Display version.

       An example session with fakechroot:

	$ export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin
	$ fakeroot -s fakechroot.save fakechroot debootstrap --variant=fakech
	root lenny /tmp/lenny

	$ fakeroot -i fakechroot.save fakechroot chroot /tmp/lenny /bin/bash
	# cd /
	# sh /usr/share/doc/fakechroot/examples/savemode.sh
	# echo deb http://ftp.debian.org/debian lenny main contrib non-free >
	# echo deb-src http://ftp.debian.org/debian lenny main contrib non-fr
	ee >> /etc/apt/sources.list
	# apt-get update
	# apt-get install adduser whiptail build-essential devscripts
	# adduser --uid 1001 user
	# cd /tmp
	# apt-get source hello
	# cd hello-*
	# debuild --preserve-env -b
	# exit

       fakechroot is a regular, non-setuid program.  It does not enhance a
       user's privileges, or decrease the system's security.

	   The shared library containing the wrapper functions.

	   The value is true for fake chroot environment.

	   The version of current fakechroot library.

	   The root directory for fake chroot environment.

	   The list of directories which are excluded from being chrooted.
	   The elements of list are separated with colon.

	   A list of command substitutions.  If a program tries to execute one
	   of the commands given (path relative to the chroot) then the
	   substitute command runs instead (path to substitute command is not

	   For example:


	   will substitute "/tmp/ldconfig-wrapper" for "/sbin/ldconfig".

	   Give as many substitute commands as you want, separated by ":"
	   (colon) characters.

	   Fakechroot is implemented by wrapping system calls.	This is
	   accomplished by setting LD_LIBRARY_PATH=/usr/lib/fakechroot and
	   LD_PRELOAD=libfakechroot.so.	 That library is loaded before the
	   system's C library, and so most of the library functions are
	   intercepted by it.  If you need to set either LD_LIBRARY_PATH or
	   LD_PRELOAD from within a fakechroot environment, it should be set
	   relative to the given paths, as in

       o   /lib/ld-linux.so.2 is always loaded from real environment.  This
	   path is hardcoded by linker for all binaries.

       o   Every command executed within fakechroot needs to be linked to the
	   same version of the C library as fakechroot itself.	If the
	   libraries in chroot are not compatible, try to use
	   --use-system-libs option.

       o   You can provide symlinks to the outside.  The symlink have to be
	   created before chroot is called.  It can be useful for accessing
	   the real /proc and /dev directory.  You can also set the
	   FAKECHROOT_EXCLUDE_PATH environment variable:

	    $ export FAKECHROOT_EXCLUDE_PATH=/tmp:/proc:/dev:/var/run

       o   Statically linked binaries doesn't work, especially ldconfig(8), so
	   you have to wrap this command with dummy version and i.e. set the
	   dpkg diversion, see: dpkg-divert(8).

       o   ldd(1) also doesn't work.  You have to use "alias
	   ldd='LD_TRACE_LOADED_OBJECTS=1'" or to use a wrapper instead.  The
	   example wrapper is available at scripts/ directory in fakechroot's
	   source package and it is located at
	   /usr/share/doc/fakechroot/examples directory.

       o   The full screen applications hangs up if /dev/tty file is not a
	   real device.	 Link /dev/tty file or whole /dev directory to the
	   real one or remove it from fake chroot environment.

       o   lckpwdf() and ulckpwdf() are ignored so passwd(1) command should

       o   Your real uid should exist in /etc/passwd.  Create it with adduser
	   --uid realuid realuser.

       o   debuild(1) cleans environment.  Use --preserve-env option to
	   prevent this behaviour.

       fakechroot is distributed under the GNU Lesser General Public License
       (LGPL 2.1 or greater).

       Copyright (c) 2003-2008 Piotr Roszatycki <dexter@debian.org>

       Copyright (c) 2006-2007 Lionel Tricon <lionel.tricon@free.fr>

       Copyright (c) 2007 Mark Eichin <eichin@metacarta.com>

       fakeroot(1), dpkg-buildpackage(1), debuild(1), debootstrap(8),

Debian				  17 Jul 2008			 FAKECHROOT(1)

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