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NAME

Queue::Mmap - Perl extension for shared queue over mmap-ed file

SYNOPSIS

        use Queue::Mmap;
        my $q = new Queue::Mmap(
                file => "file.dat",
                queue => 10, # length of queue 
                length => 20, # length one record (if data longer record, data placed in some records)
        );
        unless($q->push("abcdefghijklmnopqrstuvwxyz")){
                die "fail push";
        }

        print "length of queue is ",$q->length,"\n";
        
        my $top = $q->top;
        while(defined(my $v = $q->pop)){
                print $v,"\n";
        }
        print "no data\n";

DESCRIPTION

Queue::Mmap - Shared circle-queue over mmap-ed file.

Usefull for multy process task queue. One process(es) push task message, and other process(es) pop and execute that tasks. Access with locking(fcntl) guaranted right order without conflict. If pushed data has size greater that record len data placed in some records. If pushed data has size greater that capacity (record * queue) push has return undef.

new %params

Create new queue object

push $string

push $string into queue with block return false on failure

pop

poped top value from queue with block return undef on empty queue

top

copy top value from queue without block return undef on empty queue

drop

drop top value from queue with block return undef on failfure

length

return number of records in queue

stat

return array top - index top records bottom - index last records que_len - capacity of queue rec_len - lenth one record

aligments

Length of record align for 4 bytes. Length of file align for 4k.

TODO

Tested only on linux.

EXPORT

None by default.

SEE ALSO

AUTHOR

Ildar Efremov, <iefremov@2reallife.com<gt>

COPYRIGHT AND LICENSE

Copyright (C) 2010 by Ildar Efremov

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.

2 POD Errors

The following errors were encountered while parsing the POD:

Around line 100:

'=item' outside of any '=over'

Around line 143:

You forgot a '=back' before '=head1'