NAME

       Thread::Serialize - serialize data-structures between threads

SYNOPSIS

         use Thread::Serialize;    # export freeze() and thaw()

         use Thread::Serialize (); # must call fully qualified subs

         my $frozen = freeze( any data structure );
         any data structure = thaw( $frozen );

VERSION

       This documentation describes version 1.01.

DESCRIPTION

                         *** A note of CAUTION ***

        This module only functions if threading has been enabled when building
        Perl, or if the "forks" module has been installed on an unthreaded Perl.

                         *************************

       The Thread::Serialize module is a library for centralizing the routines used to serialize
       data-structures between threads.  Because of this central location, other modules such as
       Thread::Conveyor, Thread::Pool or Thread::Tie can benefit from the same optimilizations
       that may take place here in the future.

SUBROUTINES

       There are only two subroutines.

   freeze
        my $frozen = freeze( $scalar );

        my $frozen = freeze( @array );

       The "freeze" subroutine takes all the parameters passed to it, freezes them and returns a
       frozen representation of what was given.  The parameters can be scalar values or
       references to arrays or hashes.  Use the thaw subroutine to obtain the original data-
       structure back.

   thaw
        my $scalar = thaw( $frozen );

        my @array = thaw( $frozen );

       The "thaw" subroutine returns the data-structure that was frozen with a call to freeze.
       If called in a scalar context, only the first element of the data-structure that was
       passed, will be returned.  Otherwise the entire data-structure will be returned.

       It is up to the developer to make sure that single argument calls to freeze are always
       matched by scalar context calls to thaw.

REQUIRED MODULES

        Storable (any)
        Test::More (0.88)

INSTALLATION

       This distribution contains two versions of the code: one maintenance version for versions
       of perl < 5.014 (known as 'maint'), and the version currently in development (known as
       'blead').  The standard build for your perl version is:

        perl Makefile.PL
        make
        make test
        make install

       This will try to test and install the "blead" version of the code.  If the Perl version
       does not support the "blead" version, then the running of the Makefile.PL will *fail*.  In
       such a case, one can force the installing of the "maint" version of the code by doing:

        perl Makefile.PL maint

       Alternately, if you want automatic selection behavior, you can set the
       AUTO_SELECT_MAINT_OR_BLEAD environment variable to a true value.  On Unix-like systems
       like so:

        AUTO_SELECT_MAINT_OR_BLEAD=1 perl Makefile.PL

       If your perl does not support the "blead" version of the code, then it will automatically
       install the "maint" version of the code.

       Please note that any additional parameters will simply be passed on to the underlying
       Makefile.PL processing.

OPTIMIZATIONS

       To reduce memory and CPU usage, this module uses load.  This causes subroutines only to be
       compiled in a thread when they are actually needed at the expense of more CPU when they
       need to be compiled.  Simple benchmarks however revealed that the overhead of the
       compiling single routines is not much more (and sometimes a lot less) than the overhead of
       cloning a Perl interpreter with a lot of subroutines pre-loaded.

       To reduce the number of modules and subroutines loaded, an external Perl interpreter is
       started to determine the Storable signature at compile time.  In some situations this may
       cause a problem: please set the $Thread::Serialize::no_external_perl variable to a true
       value at compile time before loading Thread::Serialize if this causes a problem.

        BEGIN { $Thread::Serialize::no_external_perl= 1 }
        use Thread::Serialize;

KNOWN ISSUES

   Embedded Perls
       Philip Monsen reported that in the case of an embedded Perl interpreter (e.g.  in a C
       program), the use of an external executor to determine the Storable signature, causes
       problems.  This has been fixed by introducing the global variable
       $Thread::Serialize::no_external_perl (see OPTIMIZATIONS).

AUTHOR

       Elizabeth Mattijsen, <liz@dijkmat.nl>.

       Please report bugs to <perlbugs@dijkmat.nl>.

COPYRIGHT

       Copyright (c) 2002, 2003, 2004, 2010, 2012 Elizabeth Mattijsen <liz@dijkmat.nl>.  All
       rights reserved.  This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

SEE ALSO

       load, Thread::Conveyor, Thread::Pool, Thread::Tie.