Name
IPC::SRLock - Set/reset locking semantics to single thread processes
Version
This documents version v0.17.$Rev: 1 $ of IPC::SRLock
Synopsis
use IPC::SRLock;
my $config = { tempdir => 'path_to_tmp_directory', type => 'fcntl' };
my $lock_obj = IPC::SRLock->new( $config );
$lock_obj->set( k => 'some_resource_identfier' );
# This critical region of code is guaranteed to be single threaded
$lock_obj->reset( k => 'some_resource_identfier' );
Description
Provides set/reset locking methods which will force a critical region of code to run single threaded
Implements a factory pattern, three implementations are provided. The LCD option IPC::SRLock::Fcntl which works on non Unixen, IPC::SRLock::Sysv which uses System V IPC, and IPC::SRLock::Memcached which uses libmemcache
to implement a distributed lock manager
Configuration and Environment
Defines the following attributes;
debug
-
Mutable attribute if true will log lock set events at the debug level
type
-
Determines which factory subclass is loaded. Defaults to
fcntl
, can be;fcntl
,memcached
, orsysv
Subroutines/Methods
BUILDARGS
Extracts the type
attribute from those passed to the factory subclass
BUILD
Called after an instance is created this subroutine triggers the lazy evaluation of the concrete subclass
get_table
my $data = $lock_obj->get_table;
Returns a hash ref that contains the current lock table contents. The keys/values in the hash are suitable for passing to HTML::FormWidgets
list
my $array_ref = $lock_obj->list;
Returns an array of hash refs that represent the current lock table
reset
$lock_obj->reset( k => 'some_resource_key' );
Resets the lock referenced by the k
attribute.
set
$lock_obj->set( k => 'some_resource_key' );
Sets the specified lock. Attributes are:
k
-
Unique key to identify the lock. Mandatory no default
p
-
Explicitly set the process id associated with the lock. Defaults to the current process id
t
-
Set the time to live for this lock. Defaults to five minutes. Setting it to zero makes the lock last indefinitely
Diagnostics
Setting debug
to true will cause the set
methods to log the lock record at the debug level
Dependencies
Incompatibilities
The sysv
subclass type will not work on MSWin32
and cygwin
platforms
Bugs and Limitations
Testing of the memcached
subclass type is skipped on all platforms as it requires memcached
to be listening on the localhost's default memcached port localhost:11211
There are no known bugs in this module. Please report problems to the address below. Patches are welcome
Author
Peter Flanigan, <pjfl@cpan.org>
License and Copyright
Copyright (c) 2013 Peter Flanigan. All rights reserved
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic
This program is distributed in the hope that it will be useful, but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE