VLOCK-PLUGINS(5) Linux Programmer's Manual VLOCK-PLUGINS(5)NAME
vlock-plugins - plugin support for vlock
DESCRIPTION
If vlock-main(8) is compiled with plugin support its default features are very limited: it can only lock the current session and ask for
authenticiaton. However it is possible to extend this functions through plugins. These plugins are loaded when vlock-main starts and can
provide hooks that are called at certain points during the lifetime of the vlock-main process.
DEFAULT PLUGINS
The following plugins are provided when installing vlock with default options:
all
This plugin locks all sessions by disabling console switching. It is also loaded when giving the -a,--all option to vlock(1).
new
This plugin switches to a new virtual console before disabling console switching through the "all" plugin. It is also loaded when
giving the -n,--new option to vlock(1).
nosysrq
Linux only. This plugin disables the Linux SysRQ mechanism before the console switching is locked by the "all" plugin. It is also
loaded when giving the -s,--disable-sysrq option to vlock(1).
ADDITIONAL PLUGINS
The following plugins are only available if explicitely selected at build time:
caca
This plugin runs a random libcaca screensaver when the screen is locked.
WRITING PLUGINS
For information about writing plugins see the PLUGINS file in the vlock source distribution.
SEE ALSO vlock(1), vlock-main(8)AUTHORS
Frank Benkstein <frank-vlock@benkstein.net>
Linux 10 November 2007 VLOCK-PLUGINS(5)
Check Out this Related Man Page
VLOCK(1) Linux User's Manual VLOCK(1)NAME
vlock - Virtual Console lock program
SYNOPSIS
vlock [ -hv ]
vlock [ -acns ] [ -t <timeout> ] [ plugins... ]
DESCRIPTION
vlock is a program to lock one or more sessions on the Linux console. This is especially useful for Linux machines which have multiple
users with access to the console. One user may lock his or her session(s) while still allowing other users to use the system on other vir-
tual consoles. If desired, the entire console may be locked and virtual console switching disabled.
By default, only the current VC (virtual console) is locked. With the -a,--all option all VCs are locked. The locked VCs cannot be
unlocked without the invoker's password or the root password. The root password will always be able to unlock any or all sessions, unless
disabled at compile time.
Please note that it is entirely possible to completely lock yourself out of the console with the -a,--all option if you cannot remember
your password! Unless you are able to kill vlock by logging in remotely via a serial terminal or network, a hard reset is the only method
of ``unlocking'' the display.
When locking the entire console display it is sometimes still possible to kill vlock using the Secure Access Key (SAK) or other commands
that are available through the SysRq mechanism. When the -s,--disable-sysrq and -a,--all options are given the SysRq mechanism is disabled
while vlock is running. See /usr/src/linux/Documentation/sysrq.txt for more details.
vlock works for console sessions primarily. To lock the entire console display from an X session use the -n,--new option. This will make
vlock switch to an empty virtual console to lock the display.
The options -n,--new, -s,--disable-sysrq, and -t,--timeout only work if vlock is compiled with plugin support. See the PLUGINS section for
more information.
OPTIONS -a,--all
Lock all console sessions and disable VC switching.
-c,--current
Lock the current session (this is the default).
-n,--new
Switch to a new virtual console before locking all console sessions.
-s,--disable-sysrq
Disable the SysRq mechanism while consoles are locked. This option only works if the -a,--all option given.
-t,--timeout <seconds>
Specify the timeout for the screensaver plugins. See vlock-plugins(5) for more information.
-h,--help
Print a brief help message.
-v,--version
Print the version number.
ENVIRONMENT VARIABLES
The following environment variables can be used to change vlock's behavior:
USER
If this variable is when vlock is run as root (uid 0) vlock locks the screen as this user instead of root. The root password will
still be able to unlock the session, unless disabled at compile time.
VLOCK_ALL_MESSAGE
If this variable is set and all consoles are locked its contents will be used as the locking message instead of the default message.
VLOCK_CURRENT_MESSAGE
If this variable is set and only the current consoles is locked its contents will be used as the locking message instead of the
default message.
VLOCK_MESSAGE
If this variable is set its contents will be used as the locking message instead of the default. This overrides the former two
variables.
VLOCK_PLUGINS
If this variable is set it is interpreted as a space separated list of plugins that will be loaded when vlock starts additionally to
the ones listed on the command line.
VLOCK_TIMEOUT
Set this variable to specify the timeout (in seconds) after which the screen saver plugins (if any) will be invoked. If this vari-
able is unset or set to an invalid value or 0 no timeout is used. See vlock-plugins(5) for more information about plugins.
VLOCK_PROMPT_TIMEOUT
Set this variable to specify the amount of time (in seconds) you will have to enter your password at the password prompt. If this
variable is unset or set to an invalid value or 0 no timeout is used. Warning: If this value is too low, you may not be able to
unlock your session.
FILES
~/.vlockrc
This file is read by vlock on startup if it exists. All the variables mentioned above can be set here.
SECURITY
See the SECURITY file in the vlock distribution for more information.
SEE ALSO vlock-main(8), vlock-plugins(5)AUTHORS
Michael K. Johnson <http://danlj.org/mkj/>
Frank Benkstein <frank-vlock@benkstein.net>
Linux 28 July 2007 VLOCK(1)