Free locks software for linux

cnslock is a dock application (dockapp) which provides a visual indication of the states of the three "lock" buttons (caps, num, and scroll).

cnslock was written so that I could see the state of those keys as I have a wireless keyboard with no leds on it.

Usage:

Simply launch:

cnslock

If you have problems running it under a different window manager, such as fvwm or enlightenment, there is a command line argument that may help:

cnslock -w

Laplock project locks your computer or laptop using a media card such as USB memory, SD, MMC, or a Memory Stick. Once you register a unique card, the program starts xlock or xscreensaver when it is removed and stops it once it is plugged in again.
INSTALLATION
you need: udev, the userspace dev tools. This does
not work with devfs.
you can execute everything you want, but a screensaver
would be the best. so install xlock or xscreensaver
1) just type make to compile laplock.
2) type make install to install the binary to /usr/bin
and the sample conf file to /etc/
(you can type make DESTDIR=what/ever/ install to
install it for packages or so.)
3) edit /etc/laplock.conf.example and move it to
/etc/laplock.conf.
and youre done. have fun.
CONFIGURATION
in version 0.0.3 you only need 3 variables to set.
DEVICE
the device to watch. fire up udevmonitor
and plug in a card into your reader. normally
there are 3 lines with add@ and many shit.
(also the device)
UUID
close udevmonitor and go to /dev/disk/by-uuid/
there is a new file with the unique id of your
card.
EXECUTE
this command will be started, when you insert
your mastercard. xlock is very nice and works
good.
Enhancements:
- Debug mode was implemented with laplock -d.
- A lot of code cleaning was done in laplock.c and udev.h.
- An application is started with fork() instead of with system() and bash.
- getopt_long is used for parameters now.
- Nice indent schemes were added to the Makefile.

Lock keys Applet is a GNOME-applet, that shows the status of the caps-, num- and scroll-lock keys of your keyboard.
This isnt especially usefull for normal keyboards, as they got leds for that. But some keyboards (especially wireless keyboards) dont have. One more feature of the applet is that it saves the status of the lock-keys and restores it, when starting GNOME.
Installation:
The `configure shell script attempts to guess correct values for various system-dependent variables used during compilation. It uses those values to create a `Makefile in each directory of the package.
It may also create one or more `.h files containing system-dependent definitions.
Finally, it creates a shell script `config.status that you can run in the future to recreate the current configuration, a file `config.cache that saves the results of its tests to speed up reconfiguring, and a file `config.log containing compiler output (useful mainly for debugging `configure).
If you need to do unusual things to compile the package, please try to figure out how `configure could check whether to do them, and mail diffs or instructions to the address given in the `README so they can be considered for the next release.
If at some point `config.cache contains results you dont want to keep, you may remove or edit it.
The file `configure.in is used to create `configure by a program called `autoconf. You only need `configure.in if you want to change it or regenerate `configure using a newer version of `autoconf.
The simplest way to compile this package is:
1. `cd to the directory containing the packages source code and type `./configure to configure the package for your system.
If youre using `csh on an old version of System V, you might need to type `sh ./configure instead to prevent `csh from trying to execute `configure itself.
Running `configure takes awhile. While running, it prints some messages telling which features it is checking for.
2. Type `make to compile the package.
3. Optionally, type `make check to run any self-tests that come with the package.
4. Type `make install to install the programs and any data files and documentation.
5. You can remove the program binaries and object files from the source code directory by typing `make clean. To also remove the files that `configure created (so you can compile the package for a different kind of computer), type `make distclean.
There is also a `make maintainer-clean target, but that is intended mainly for the packages developers. If you use it, you may have to get all sorts of other programs in order to regenerate files that came with the distribution.
Enhancements:
- (almost) completly renamed everything to lock-keys-applet

vp-usb-lock is a Linux kernel driver and PAM module that utilizes the PC wireless USB lock and makes it possible to use it as authentication method for your Linux box.
It is easy to install, but needs access to the sources of the kernel and PAM to build correctly. It has been tested under Fedora Core 2 with a custom made 2.6.7-1.494.2.2 kernel, but it should also work with other kernel versions and distributions.
Enhancements:
- A lock daemon was added.
- A compilation error that was introduced lately by some changes to the Linux kernel was fixed.
- Support for kernel 2.4.x versions was added.

Tie::DB_Lock Perl module can tie hashes to databases using shared and exclusive locks.

SYNOPSIS

use Tie::DB_Lock;
use DB_File;

tie(%hash, Tie::DB_Lock, $filename, rw); # Open for writing
$hash{key} = value;
untie %hash;

tie(%hash2, Tie::DB_Lock, $filename); # Default is read-only
print("Value is $hash2{key}n");
untie %hash;

This is a front-end for the DB_File package.

If you tie a hash in read-only mode, this module puts a shared lock on the database file, copies it to a temporary file, unlocks the original database, and then ties the tempfile using DB_File.

If you tie the hash in read-write mode, we put an exclusive lock on the database and tie it directly using DB_File.

The reason I copy the whole file every time I read from it is that this allows the program to read from the file for as long as it wants to, without interfering with other peoples writes. This works well if you typically have long, sustained reads, and short, bursty writes. See the README file for help in deciding whether you want to use this package.

You dont always need to call untie() explicitly - it will be called for you when %hash goes out of scope. And if all goes as planned, youll never know the temporary file ever existed, since it will evaporate when %hash goes away.

File::NFSLock is a Perl module to do NFS (or not) locking.
SYNOPSIS
use File::NFSLock qw(uncache);
use Fcntl qw(LOCK_EX LOCK_NB);
my $file = "somefile";
### set up a lock - lasts until object looses scope
if (my $lock = new File::NFSLock {
file => $file,
lock_type => LOCK_EX|LOCK_NB,
blocking_timeout => 10, # 10 sec
stale_lock_timeout => 30 * 60, # 30 min
}) {
### OR
### my $lock = File::NFSLock->new($file,LOCK_EX|LOCK_NB,10,30*60);
### do write protected stuff on $file
### at this point $file is uncached from NFS (most recent)
open(FILE, "+<<less