NAME

forks::shared - drop-in replacement for Perl threads::shared with forks()

SYNOPSIS

  use forks;
  use forks::shared;

  my $variable : shared;
  my @array    : shared;
  my %hash     : shared;

  share( $variable );
  share( @array );
  share( %hash );

  lock( $variable );
  cond_wait( $variable );
  cond_wait( $variable, $lock_variable );
  cond_timedwait( $variable, abs time );
  cond_timedwait( $variable, abs time, $lock_variable );
  cond_signal( $variable );
  cond_broadcast( $variable );
  
  bless( $variable, class name );

DESCRIPTION

The "forks::shared" pragma allows a developer to use shared variables with threads (implemented with the "forks" pragma) without having to have a threaded perl, or to even run 5.8.0 or higher.

EXPORT

share, cond_wait, cond_timedwait, cond_signal, cond_broadcast, is_shared, bless

See "EXPORT" in threads::shared for more information.

OBJECTS

forks::shared exports a versio of bless() that works on shared objects, such that blessings propagate across threads. See threads::shared for usage information and the forks test suite for additional examples.

NOTES

As of threads::shared 1.01, the splice function has not yet been implememted for arrays; however, forks::shared fully supports splice on shared arrays.

KNOWN PROBLEMS

These problems are known and will be fixed in the future:

test-suite exits in a weird way

Although there are no errors in the test-suite, the test harness sometimes thinks there is something wrong because of an unexpected exit() value. This is an issue with Test::More's END block, which wasn't designed to co-exist with a threads environment and forked processes. Hopefully, that module will be patched in the future, but for now, the warnings are harmless and may be safely ignored.

shared variable in push() on shared array bombs

For some reason, using a bare shared variable as a parameter in a push() on a shared array, bombs. This can be fixed by adding .'' to the shared variable.

  push( @shared,$shared );    # bombs
  push( @shared,$shared.'' ); # works

This could be a generic problem with tie() in Perl, judging from some very recent discussion on p5p.

CREDITS

threads::shared

For some of the XS code used for forks::shared exported bless function.

ORIGINAL AUTHOR CREDITS

Arthur Bergman for Hook::Scope (from which I swiped the code to have locked variables automatically unlock upon leaving the scope they were locked in) and threads::shared (from which I swiped the code to create references from the parameter list passed to a subroutine).

CURRENT MAINTAINER

Eric Rybski <rybskej@yahoo.com>.

ORIGINAL AUTHOR

Elizabeth Mattijsen, <liz@dijkmat.nl>.

COPYRIGHT

Copyright (c) 2005-2006 Eric Rybski <rybskej@yahoo.com>, 2002-2004 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

threads::shared, forks, forks::BerkeleyDB::shared.