Oh Monks, I bring to you a riddle. When is_shared, not shared?

I have a threaded program in which I create a shared hash in main:

use threads qw(stringify);
use threads::shared;
my %contacts : shared;

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I load a hashref into the hash in a sub-routine sharing each level as such:

$contacts{$contact} = &share( {} );
share( $contacts{$contact}{'a'} );
share( $contacts{$contact}{'inc_dnd'} );
share( $contacts{$contact}{'lock'} );
$contacts{$contact}{'a'} = 1;
$contacts{$contact}{'inc_dnd'} = &share( {} );
$contacts{$contact}{'lock'} = 0;

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In a thread, I try to execute

lock( $contacts{$user_id} );

I receive the following error

lock can only be used on shared values at get_contacts_pool_photos.pl line 170.

However, if I run the program in the debugger I can verify that I can access the hash and that it contains the data that I expect

  DB<2> print Dumper $contacts{$user_id}
$VAR1 = {
          'inc_dnd' => {},
          'a' => '1',
          'lock' => '0',
          'd' => '/tmp'
        };

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Futhermore, if I check to see if the variable is shared, I find that it is.

170:            lock( $contacts{$user_id} );
  DB<2> print is_shared($contacts{$user_id})
226839368
  DB<3> n
lock can only be used on shared values at get_contacts_pool_photos.pl 
+line 170.
 at get_contacts_pool_photos.pl line 170
        main::get_contacts_pool_photos() called at get_contacts_pool_p
+hotos.pl line 93

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So Monks, I ask, is it shared or not?

How should I fix my problem?

Thanks in advance for your guidance.

lbe

In reply to thread::shared - shared but not shared? by learnedbyerror

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