1MDC(3)                User Contributed Perl Documentation               MDC(3)
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NAME

6       Log::Log4perl::MDC - Mapped Diagnostic Context
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DESCRIPTION

9       Log::Log4perl allows loggers to maintain global thread-specific data,
10       called the Nested Diagnostic Context (NDC) and Mapped Diagnostic
11       Context (MDC).
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13       The MDC is a simple thread-specific hash table, in which the
14       application can stuff values under certain keys and retrieve them later
15       via the "%X{key}" placeholder in
16       "Log::Log4perl::Layout::PatternLayout"s.
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18       Log::Log4perl::MDC->put($key, $value);
19           Store a value $value under key $key in the map.
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21       my $value = Log::Log4perl::MDC->get($key);
22           Retrieve the content of the map under the specified key.  Typically
23           done by %X{key} in "Log::Log4perl::Layout::PatternLayout".  If no
24           value exists to the given key, "undef" is returned.
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26       my $text = Log::Log4perl::MDC->remove();
27           Delete all entries from the map.
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29       Log::Log4perl::MDC->get_context();
30           Returns a reference to the hash table.
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32       Please note that all of the methods above are class methods, there's no
33       instances of this class. Since the thread model in perl 5.8.0 is "no
34       shared data unless explicitly requested" the data structures used are
35       just global (and therefore thread-specific).
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LICENSE

38       Copyright 2002-2013 by Mike Schilli <m@perlmeister.com> and Kevin Goess
39       <cpan@goess.org>.
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41       This library is free software; you can redistribute it and/or modify it
42       under the same terms as Perl itself.
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AUTHOR

45       Please contribute patches to the project on Github:
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47           http://github.com/mschilli/log4perl
48
49       Send bug reports or requests for enhancements to the authors via our
50
51       MAILING LIST (questions, bug reports, suggestions/patches):
52       log4perl-devel@lists.sourceforge.net
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54       Authors (please contact them via the list above, not directly): Mike
55       Schilli <m@perlmeister.com>, Kevin Goess <cpan@goess.org>
56
57       Contributors (in alphabetical order): Ateeq Altaf, Cory Bennett, Jens
58       Berthold, Jeremy Bopp, Hutton Davidson, Chris R. Donnelly, Matisse
59       Enzer, Hugh Esco, Anthony Foiani, James FitzGibbon, Carl Franks, Dennis
60       Gregorovic, Andy Grundman, Paul Harrington, Alexander Hartmaier  David
61       Hull, Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter,
62       Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope, Lars
63       Thegler, David Viner, Mac Yang.
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67perl v5.38.0                      2023-07-20                            MDC(3)
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