Re: FileHandles and threads

[Anonymous Monk]

hello

i have used the code and comment, because my problem was a little similar. i need to access to a big file (6Go / 12M protein records) to search for fuzzy similary

so i give my solution, it's a good start and maybe it will be useful to someone

regards

yovoa

 #! perl -slw
use strict;
use warnings;
use threads;
use Thread::Queue;


my $file="/path_to_the_file" ;
our $file_handler ;
our $ref_file_handler ;
my ( $process_1 , $process_2 , $process_3 ) ;
my $flag_on_file = Thread::Queue->new ;


# main
open $file_handler, '<', $file or warn "$file : $!" and die;
$flag_on_file->enqueue(fileno($file_handler));

# threads creation
$process_1 = threads->new( \&my_sub );
$process_2 = threads->new( \&my_sub );
$process_3 = threads->new( \&my_sub );

# waiting for all threads to stop before exit
$process_1->join;
$process_2->join;
$process_3->join;

# end main


# sub
sub my_sub
{
    my( $fileno ) = $flag_on_file->dequeue ;
    open $ref_file_handler, "<&=$fileno" or warn $! and die;
for ( 1..10 )
    {
    # do something with the file
    # exemple
    print threads->self->tid.": ".scalar <$ref_file_handler> ;
    }
    close $ref_file_handler;
    $flag_on_file->enqueue(fileno($file_handler));
    # do something with data
}


exit;