in reply to Locking hash values

You can sorta get this to work like so: 
my $scalar : shared = 0;
my %hash;

$hash{key} = \$scalar;

lock $hash{key};

[download]

I'm not sure how reliable that is when you start new threads though. You're probably better off just sticking with a few shared scalars in my opinion. Perl's threading isn't one of it's strongest features. At least you're not stuck with IPC.

-Paul

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Re^2: Locking hash values
by bucky0 (Initiate) on Dec 18, 2006 at 18:25 UTC
    Perhaps I'm doing something wrong, but that code fails out as well...perl's threading hurts me, this should be a simple thing to do. Not only that, it's mentioned in the POD as working.
[reply]

      I think that should be 

      lock ${$hash{key}};

      [download]

      The idea is that $scalar is shared, and therefore lockable.

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[d/l]
[select]
        To continue with this theme why not to share a ref to a hash. Like so: 
        ...
use threads;
use threads::shared;
...

my $href : shared;
$href = &share({});
...

# Lock block
{
  lock $href;
  $href->{mykey} = 'myval';
}
...

        [download]
        For more see perldoc threads::shared.

        - BR

[reply]
[d/l]
        That works out well. It's weird that it's mentioned in the POD as something that should work without all of this hoopla. The design behind perl threads _really_ wants to make it hard to share data, it seems.
[reply]

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