=pod
=head1 SUMMARY
IPC::Locker provides a server for locks and a Perl package for clients to
access that server. The result is that clients can access named locks on a
Internet wide basis, solving critical section problems without the mess of
NFS or other file locking techniques.
The latest version is available from CPAN and from
L<
https://www.veripool.org/ipc-locker>.
=head1 EXAMPLE
use IPC::Locker;
# ...
my $lock = IPC::Locker->lock(host=>'example.std.com');
# ... Critical section ...
$lock->unlock;
=head1 INSTALLATION
=head2 Build and Install the Package
=head3 Install from CPAN:
cpan install IPC::Locker
=head3 Or, build from sources:
# Obtain distribution kit
git clone
[email protected]:veripool/IPC-Locker.git
# Build
cd IPC-Locker
git pull
perl Makefile.PL
make
make test
make install
=head2 Install the Daemons
You may wish to install C<lockerd> and C<pidstatd> in a init.rc file so
that it is run at system startup. Depending on your distribution, you may
be able to just:
cp init.d/lockerd /etc/init.d/lockerd # On one server only
cp init.d/pidstatd /etc/init.d/pidstatd # On all machines
Edit paths in above to point to /usr/bin instead of /usr/local/bin, if needed.
service lockerd start # On one server only
service pidstatd start # On all machines
chkconfig lockerd on # On one server only
chkconfig pidstatd on # On all machines
If you get "This account is currently not available." you need to change
the daemon account from a shell of /sbin/nologin to /sbin/bash.
=head2 Nagios
If you are using Nagios
http://www.nagios.org, sample scripts to check the
daemons are included in the nagios subdirectory.
=head1 DOCUMENTATION
IPC::Locker provides the following programs/packages:
=head2 lockerd
C<lockerd> is the daemon that supports IPC::Locker. See C<man
lockerd> after installation.
=head2 IPC::PidStat
C<IPC::PidStat> is a Perl package which answers the question, "is pid X
running on host Y?". See C<man IPC::PidStat> after installation.
=head2 pidstat
C<pidstat> is a program which answers the question, "is pid X running on
host Y?". See C<man pidstat> after installation.
=head2 pidstatd
C<pidstat> is the daemon that supports C<IPC::PidStat> and C<pidstat>. See
C<man pidstatd> after installation.
=head2 pidwatch
C<pidwatch> is a program which starts other programs, and kill that program
when another job exists. See C<man pidwatch> after installation.
=head2 uriexec
C<uriexec> is a simple wrapper which allows executing a command which is
quoted using URI escapes. This prevents layered shells from interpreting
special characters. See C<man uriexec> after installation.
=head2 check_lockerd and check_pidstatd
C<check_lockerd> and C<check_pidstatd> are Nagios plugins to check
C<lockerd> and C<pidstatd>. See the Nagios documentation at
https://www.nagios.org for information on installing plugins.
=head1 LICENSE
This package is Copyright 1999-2019 by Wilson Snyder <
[email protected]>.
This program is free software; you can redistribute it and/or modify it
under the terms of either the GNU Lesser General Public License Version 3
or the Perl Artistic License Version 2.0. This code is provided with no
warranty of any kind, and is used entirely at your own risk.
