NAME Apache::Singleton - Singleton class for mod_perl SYNOPSIS package Printer; use base qw(Apache::Singleton); # same: default is per Request package Printer::PerRequest; use base qw(Apache::Singleton::Request); package Printer::PerProcess; use base qw(Apache::Singleton::Process); package Printer::PerServer; use base qw(Apache::Singleton::Server); DESCRIPTION Apache::Singleton works the same as Class::Singleton, but with various object lifetime (scope). See the Class::Singleton manpage first. OBJECT LIFETIME By iniheriting one of the following sublasses of Apache::Singleton, you can change the scope of your object. Request use base qw(Apache::Singleton::Request); One instance for one request. Apache::Singleton will remove intstance on each request. Implemented using mod_perl "pnotes" API. This is the default scope, so inheriting from Apache::Singleton would do the same effect. Process use base qw(Apache::Singleton::Process); One instance for one httpd process. Implemented using package global. Notice this is the same beaviour with Class::Singleton ;) Server use base qw(Apache::Singleton::Server); One instance for one server (across all httpd processes). Implemented using Cache::SharedMemoryCache (IPC). Note that multiple process cannot share blessed reference without serialization, so *One instance for one server* is just an idea. What it means is, one instance for one process, and multiple instances with shared data across one server. See t/05_server.t in this module distribution for what it exactly means. AUTHOR Original idea by Matt Sergeant and Perrin Harkins . Code by Tatsuhiko Miyagawa This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. SEE ALSO the Apache::Singleton::Request manpage, the Apache::Singleton::Process manpage, the Apache::Singleton::Server manpage, the Class::Singleton manpage, the Cache::SharedMemoryCache manpage