Monks, I am attempting to allow a child to update a hash value that the parent can later reference. This appears possible using forks::shared. Here is a trivial example of a parent and child sharing an integer variable.

use forks;
use forks::shared;

my $GLOBALPRICE : shared;
share ($GLOBALPRICE);

my $pid = fork ();
if (!$pid) {       # child 
    $GLOBALPRICE = 100; exit 0;
} elsif ($pid)  {  # daddy
    sleep (2);
    print "Global Oils Price is now: " . $GLOBALPRICE . " dollars\n";
}

[download]

However, if I turn the shared variable into a hash reference, the parent will not see the child's change. For example: 

use forks;
use forks::shared;
my %GLOBALHASH : shared;

share (%GLOBALHASH);

my $pid = fork ();
if (!$pid) {      # child 
    $GLOBALHASH->{OILPRICE} = 100; exit 0;
} elsif ($pid)  {  # daddy
    sleep (2);
    print "Global Oils Price is now: " . $GLOBALHASH->{OILPRICE} . " d
+ollars\n";
}

[download]
In this second case, the parent cannot see the OILPRICE key. Could someone explain how to modify the hash example so that the parent and child can properly share a hash?

In reply to forked::shared with hashes? by GriffinP

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