Hello, I'm having an issue with sharing data between a thread and the calling program. The following code creates three objects, and each object starts a thread that is supposed to do something and then report a result back to the main section. I am sharing $self->{x2} inside the startThread procedure and I was hoping that each instance of the object would share its own $self.

#!/usr/bin/perl

#-----------------------------------------------------
package p1;
#-----------------------------------------------------

use strict;
use warnings;
use threads;
use threads::shared;

sub new {
  my $class = shift;
  my $self  = { @_ };
  $self->{x2} = $self->{x1};
  return bless $self, $class;
}


sub startThread {

  my $self = shift;
  my $thr;

  share ($self->{x2});

  sub test {
    my $x1 = shift;
    my $r = int(rand()*1000);
    print "$x1: starting thread r=$r \$self{x1}=$self->{x1}\n";
    sleep $r/100;
    print "$x1: setting variable\n";
    $self->{x2} = $r;
    sleep 10;
    print "$x1: closing thread \$self{x2}=$self->{x2}\n";
    threads->exit();
  };

  print "threads->create \$self{x1}=$self->{x1}\n";
  $thr = threads->create('test', $self->{x1});
  $thr->detach();
}


#-----------------------------------------------------
package main;
#-----------------------------------------------------

use strict;
use warnings;

my $objA = p1->new( x1 => 'A' );
my $objB = p1->new( x1 => 'B' );
my $objC = p1->new( x1 => 'C' );

print "    $objA->{x1}=$objA->{x2} $objB->{x1}=$objB->{x2} $objC->{x1}
+=$objC->{x2}\n";

$objA->startThread();
$objB->startThread();
$objC->startThread();

for (my $i = 1; $i < 15; $i++) {
  print "    $objA->{x1}=$objA->{x2} $objB->{x1}=$objB->{x2} $objC->{x
+1}=$objC->{x2}\n";
  sleep 2;
}
[download]

When I run this, I get, for example, the following output:

Variable "$self" will not stay shared at ./test1.pl line 30.
    A=A B=B C=C
threads->create $self{x1}=A
threads->create $self{x1}=B
threads->create $self{x1}=C
    A=A B=B C=C
C: starting thread r=85 $self{x1}=A
B: starting thread r=289 $self{x1}=A
C: setting variable
A: starting thread r=861 $self{x1}=A
    A=85 B=B C=C
B: setting variable
    A=289 B=B C=C
    A=289 B=B C=C
A: setting variable
    A=289 B=B C=C
C: closing thread $self{x2}=861
    A=861 B=B C=C
B: closing thread $self{x2}=861
    A=861 B=B C=C
    A=861 B=B C=C
    A=861 B=B C=C
A: closing thread $self{x2}=861
    A=861 B=B C=C
    A=861 B=B C=C
    A=861 B=B C=C
    A=861 B=B C=C
    A=861 B=B C=C

In this example, I was hoping to see "A=861 B=289 C=85" at the end. It seems that the $self belonging to the first object created (objA) is shared between all three threads and the calling program. I don't need any sharing between the threads, just separate sharing between each object instance and its calling program. How can I achieve that? Some help on this would be greatly appreciated.

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