Log::Message man page on Archlinux

Man page or keyword search:  
man Server   11224 pages
apropos Keyword Search (all sections)
Output format
Archlinux logo
[printable version]

Log::Message(3perl)    Perl Programmers Reference Guide	   Log::Message(3perl)

       Log::Message - A generic message storing mechanism;

	   use Log::Message private => 0, config => '/our/cf_file';

	   my $log = Log::Message->new(	   private => 1,
					   level   => 'log',
					   config  => '/my/cf_file',

	   $log->store('this is my first message');

	   $log->store(	   message => 'message #2',
			   tag	   => 'MY_TAG',
			   level   => 'carp',
			   extra   => ['this is an argument to the handler'],

	   my @last_five_items = $log->retrieve(5);

	   my @items = $log->retrieve( tag     => qr/my_tag/i,
				       message => qr/\d/,
				       remove  => 1,

	   my @items = $log->final( level => qr/carp/, amount => 2 );

	   my $first_error = $log->first()

	   # croak with the last error on the stack

	   # empty the stack

       Log::Message is a generic message storage mechanism.  It allows you to
       store messages on a stack -- either shared or private -- and assign
       meta-data to it.	 Some meta-data will automatically be added for you,
       like a timestamp and a stack trace, but some can be filled in by the
       user, like a tag by which to identify it or group it, and a level at
       which to handle the message (for example, log it, or die with it)

       Log::Message also provides a powerful way of searching through items by
       regexes on messages, tags and level.

       There are 4 modules of interest when dealing with the Log::Message::*

	   Log::Message provides a few methods to manipulate the stack it
	   keeps.  It has the option of keeping either a private or a public
	   stack.  More on this below.

	   These are individual message items, which are objects that contain
	   the user message as well as the meta-data described above.  See the
	   Log::Message::Item manpage to see how to extract this meta-data and
	   how to work with the Item objects.  You should never need to create
	   your own Item objects, but knowing about their methods and
	   accessors is important if you want to write your own handlers. (See

	   These are a collection of handlers that will be called for a level
	   that is used on a Log::Message::Item object.	 For example, if a
	   message is logged with the 'carp' level, the 'carp' handler from
	   Log::Message::Handlers will be called.  See the
	   Log::Message::Handlers manpage for more explanation about how
	   handlers work, which one are available and how to create your own.

	   Per Log::Message object, there is a configuration required that
	   will fill in defaults if the user did not specify arguments to
	   override them (like for example what tag will be set if none was
	   provided), Log::Message::Config handles the creation of these

	   Configuration can be specified in 4 ways:

	   ·   As a configuration file when you "use Log::Message"

	   ·   As arguments when you "use Log::Message"

	   ·   As a configuration file when you create a new Log::Message
	       object.	(The config will then only apply to that object if you
	       marked it as private)

	   ·   As arguments when you create a new Log::Message object.

	       You should never need to use the Log::Message::Config module
	       yourself, as this is transparently done by Log::Message, but
	       its manpage does provide an explanation of how you can create a
	       config file.

       When using Log::Message, or creating a new Log::Message object, you can
       supply various options to alter its behaviour.  Of course, there are
       sensible defaults should you choose to omit these options.

       Below an explanation of all the options and how they work.

	   The path to a configuration file to be read.	 See the manpage of
	   Log::Message::Config for the required format

	   These options will be overridden by any explicit arguments passed.

	   Whether to create, by default, private or shared objects.  If you
	   choose to create shared objects, all Log::Message objects will use
	   the same stack.

	   This means that even though every module may make its own $log
	   object they will still be sharing the same error stack on which
	   they are putting errors and from which they are retrieving.

	   This can be useful in big projects.

	   If you choose to create a private object, then the stack will of
	   course be private to this object, but it will still fall back to
	   the shared config should no private config or overriding arguments
	   be provided.

	   Log::Message makes use of another module to validate its arguments,
	   which is called Params::Check, which is a lightweight, yet powerful
	   input checker and parser. (See the Params::Check manpage for

	   The verbose setting will control whether this module will generate
	   warnings if something improper is passed as input, or merely
	   silently returns undef, at which point Log::Message will generate a

	   It's best to just leave this at its default value, which is '1'

       tag The tag to add to messages if none was provided. If neither your
	   config, nor any specific arguments supply a tag, then Log::Message
	   will set it to 'NONE'

	   Tags are useful for searching on or grouping by. For example, you
	   could tag all the messages you want to go to the user as 'USER
	   ERROR' and all those that are only debug information with 'DEBUG'.

	   At the end of your program, you could then print all the ones
	   tagged 'USER ERROR' to STDOUT, and those marked 'DEBUG' to a log

	   "level" describes what action to take when a message is logged.
	   Just like "tag", Log::Message will provide a default (which is
	   'log') if neither your config file, nor any explicit arguments are
	   given to override it.

	   See the Log::Message::Handlers manpage to see what handlers are
	   available by default and what they do, as well as to how to add
	   your own handlers.

	   This indicates whether or not to automatically remove the messages
	   from the stack when you've retrieved them.  The default setting
	   provided by Log::Message is '0': do not remove.

	   This indicates whether messages should always be fetched in
	   chronological order or not.	This simply means that you can choose
	   whether, when retrieving items, the item most recently added should
	   be returned first, or the one that had been added most long ago.

	   The default is to return the newest ones first

       This creates a new Log::Message object; The parameters it takes are
       described in the "Options" section below and let it just be repeated
       that you can use these options like this:

	   my $log = Log::Message->new( %options );

       as well as during "use" time, like this:

	   use Log::Message option1 => value, option2 => value

       There are but 3 rules to keep in mind:

       ·   Provided arguments take precedence over a configuration file.

       ·   Arguments to new take precedence over options provided at "use"

       ·   An object marked private will always have an empty stack to begin

       This will create a new Item object and store it on the stack.

       Possible arguments you can give to it are:

	   This is the only argument that is required. If no other arguments
	   are given, you may even leave off the "message" key. The argument
	   will then automatically be assumed to be the message.

       tag The tag to add to this message. If not provided, Log::Message will
	   look in your configuration for one.

	   The level at which this message should be handled. If not provided,
	   Log::Message will look in your configuration for one.

	   This is an array ref with arguments passed to the handler for this
	   message, when it is called from store();

	   The handler will receive them as a normal list

       store() will return true upon success and undef upon failure, as well
       as issue a warning as to why it failed.

       This will retrieve all message items matching the criteria specified
       from the stack.

       Here are the criteria you can discriminate on:

       tag A regex to which the tag must adhere. For example "qr/\w/".

	   A regex to which the level must adhere.

	   A regex to which the message must adhere.

	   Maximum amount of errors to return

	   Return in chronological order, or not?

	   Remove items from the stack upon retrieval?

       In scalar context it will return the first item matching your criteria
       and in list context, it will return all of them.

       If an error occurs while retrieving, a warning will be issued and undef
       will be returned.

       This is a shortcut for retrieving the first item(s) stored on the
       stack. It will default to only retrieving one if called with no
       arguments, and will always return results in chronological order.

       If you only supply one argument, it is assumed to be the amount you
       wish returned.

       Furthermore, it can take the same arguments as "retrieve" can.

       This is a shortcut for retrieving the last item(s) stored on the stack.
       It will default to only retrieving one if called with no arguments, and
       will always return results in reverse chronological order.

       If you only supply one argument, it is assumed to be the amount you
       wish returned.

       Furthermore, it can take the same arguments as "retrieve" can.

       This removes all items from the stack and returns them to the caller

       Log::Message::Item, Log::Message::Handlers, Log::Message::Config

       This module by Jos Boumans <kane@cpan.org>.

       Thanks to Ann Barcomb for her suggestions.

       This module is copyright (c) 2002 Jos Boumans <kane@cpan.org>.  All
       rights reserved.

       This library is free software; you may redistribute and/or modify it
       under the same terms as Perl itself.

perl v5.18.2			  2014-01-06		   Log::Message(3perl)

List of man pages available for Archlinux

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net