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Memory mapping for Perl

File::Map

File::Map is a module that maps files or anonymous memory into perl variables.

Advantages of memory mapping

  • Unlike normal perl variables, mapped memory is shared between threads or forked processes.

  • It is an efficient way to slurp an entire file. Unlike for example File::Slurp, this module returns almost immediately, loading the pages lazily on access. This means you only 'pay' for the parts of the file you actually use.

  • Perl normally never returns memory to the system while running, mapped memory can be returned.

Advantages of this module over other similar modules Safety and Speed This module is safe yet fast. Alternatives are either fast but can cause segfaults or loose the mapping when not used correctly, or are safe but rather slow. File::Map is as fast as a normal string yet safe.

Simplicity It offers a more simple interface targeted at common usage patterns

  • Files are mapped into a variable that can be read just like any other variable, and it can be written to using standard Perl techniques such as regexps and "substr".

  • Files can be mapped using a set of simple functions. No weird constants or 6 argument functions.

  • It will automatically unmap the file when the scalar gets destroyed. This works correctly even in multithreaded programs.

Portability File::Map supports both Unix and Windows.

Thread synchronization It has built-in support for thread synchronization.

INSTALLATION

To install this module, run the following commands:

perl Build.PL
./Build
./Build test
./Build install

SUPPORT AND DOCUMENTATION

After installing, you can find documentation for this module with the perldoc command.

perldoc File::Map

You can also look for information at:

RT, CPAN's request tracker
    http://rt.cpan.org/NoAuth/Bugs.html?Dist=File-Map

AnnoCPAN, Annotated CPAN documentation
    http://annocpan.org/dist/File-Map

CPAN Ratings
    http://cpanratings.perl.org/d/File-Map

Search CPAN
    http://search.cpan.org/dist/File-Map

COPYRIGHT AND LICENCE

Copyright (C) 2008 Leon Timmermans

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