How should I fix my problem? 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.

Some thoughts, as I see a similar problem when seting up hashes for Tk programs.

My guess is that since you already declared second level hash elements, the first key to the hash gets a value that is another subhash. Its a common error in setting up deep hashes that gives a common error "Can't use string ("1") as a HASH ref while "strict refs"" in conventional programs.

When you have 

$contacts{$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;
[download]

In a thread, I try to execute
lock( $contacts{$user_id} );

[download]
Because of the way you have the hash's first key setup, $contacts{$user_id} evaluates to a hashref, not a scalar.

You might try 

share( $contacts{$contact}{'user_id'} );

[download]
or you can verify in your code by the threads:shared method 
is_shared ( $contacts{$user_id} )

[download]

I run into this problem all the time with hashes in Tk, and that is what I do, but there may be better solutions.

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

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

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