1 IPC::Locker
*************

This is the IPC::Locker Perl Package.

1.1 Copyright
=============

This package is Copyright 1999-2007 by Wilson Snyder
<wsnyder@wsnyder.org>.

   You may distribute under the terms of either the GNU General Public
License or the Perl Artistic License, as specified in the Perl README
file.

   This code is provided with no warranty of any kind, and is used
entirely at your own risk.

1.2 Description
===============

This package provides a server for locks and a package for clients to
access that server.  The result is that clients can access named locks
on a Internet wide bases, solving critical section problems without the
mess of NFS or other file locking techniques.

1.2.1 IPC::Locker
-----------------

IPC::Locker is a Perl package which allows cross cluster locking.  For
example:

       my $lock = IPC::Locker->lock(host=>'example.std.com');
       ... Critical section ...
       $lock->unlock();

   See `man IPC::Locker' after installation.

1.2.2 lockerd
-------------

lockerd is the daemon that supports IPC::Locker. See `man lockerd'
after installation.

1.2.3 IPC::PidStat
------------------

IPC::PidStat is a Perl package which answers the question, "is pid X
running on host Y?".  See `man IPC::PidStat' after installation.

1.2.4 pidstat
-------------

pidstat is a program which answers the question, "is pid X running on
host Y?".  See `man pidstat' after installation.

1.2.5 pidstatd
--------------

pidstat is the daemon that supports IPC::PidStat and pidstat. See `man
pidstatd' after installation.

1.2.6 pidwatch
--------------

pidwatch is a program which starts other programs, and kill that program
when another job exists.  See `man pidwatch' after installation.

1.2.7 uriexec
-------------

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 `man uriexec' after installation.

1.2.8 check_lockerd and check_pidstatd
--------------------------------------

check_lockerd and check_pidstatd are Nagios plugins to check lockerd
and pidstatd.  See the Nagios documentation `http://www.nagios.org' for
information on installing plugins.

1.3 Obtaining Distribution
==========================

The latest version is available at `http://www.perl.org/CPAN/'

   Download the latest package from that site, and decompress.  `gunzip
IPC::Locker_version.tar.gz ; tar xvf IPC::Locker_version.tar'

1.4 Supported Systems
=====================

This version of IPC::Locker has been built and tested on:

   * i386-linux

   * sparc-sun-solaris2.7

   It should run on any system with perl and TCP/IP socketing.

1.5 Installation
================

  1. `cd' to the directory containing this README notice.

  2. Type `perl Makefile.PL' to configure IPC::Locker for your system.

  3. Type `make' to compile IPC::Locker.

  4. Type `make test' to check the compilation.

  5. Type `make install' to install the programs and any data files and
     documentation.

  6. You may wish to install `lockerd' and `pidstatd' in a init.rc file
     so that it is run at system startup.  Depending on your
     distribution, you may be able to just copy the examples in
     init.d/lockerd to /etc/init.d, and type `chkconfig pidstatd on'
     and `chkconfig lockerd on'.

  7. If you are using Nagios (`http://www.nagios.org'), sample scripts
     to check the daemons are included in the nagios subdirectory.